diff --git a/doc/Pacemaker_Remote/en-US/Book_Info.xml b/doc/Pacemaker_Remote/en-US/Book_Info.xml index 426599ecf8..a26494e742 100644 --- a/doc/Pacemaker_Remote/en-US/Book_Info.xml +++ b/doc/Pacemaker_Remote/en-US/Book_Info.xml @@ -1,56 +1,75 @@ %BOOK_ENTITIES; ]> Pacemaker Remote - Extending High Availablity into Virtual Nodes - 1 + Scaling High Availablity Clusters + + 4 0 The document exists as both a reference and deployment guide for the Pacemaker Remote service. - The KVM and Linux Container walk-through tutorials will use: + The example commands in this document will use: &DISTRO; &DISTRO_VERSION; as the host operating system - Pacemaker Remote to perform resource management within virtual nodes + Pacemaker Remote to perform resource management within guest nodes and remote nodes - libvirt to manage KVM and LXC virtual nodes + KVM for virtualization - Corosync to provide messaging and membership services on the host nodes + libvirt to manage guest nodes - Pacemaker to perform resource management on host nodes + Corosync to provide messaging and membership services on cluster nodes + + + + + Pacemaker to perform resource management on cluster nodes + + + + + pcs as the cluster configuration toolset + The concepts are the same for other distributions, + virtualization platforms, toolsets, and messaging + layers, and should be easily adaptable. diff --git a/doc/Pacemaker_Remote/en-US/Ch-Alternatives.txt b/doc/Pacemaker_Remote/en-US/Ch-Alternatives.txt new file mode 100644 index 0000000000..d2fd9f42fd --- /dev/null +++ b/doc/Pacemaker_Remote/en-US/Ch-Alternatives.txt @@ -0,0 +1,77 @@ += Alternative Configurations = + +These alternative configurations may be appropriate in limited cases, such as a +test cluster, but are not the best method in most situations. They are +presented here for completeness and as an example of pacemaker's flexibility +to suit your needs. + +== Virtual Machines as Cluster Nodes == + +The preferred use of virtual machines in a pacemaker cluster is as a +cluster resource, whether opaque or as a guest node. However, it is +possible to run the full cluster stack on a virtual node instead. + +This is commonly used to set up test environments; a single physical host +(that does not participate in the cluster) runs two or more virtual machines, +all running the full cluster stack. This can be used to simulate a +larger cluster for testing purposes. + +In a production environment, fencing becomes more complicated, especially +if the underlying hosts run any services besides the clustered VMs. +If the VMs are not guaranteed a minimum amount of host resources, +CPU and I/O contention can cause timing issues for cluster components. + +Another situation where this approach is sometimes used is when +the cluster owner leases the VMs from a provider and does not have +direct access to the underlying host. The main concerns in this case +are proper fencing (usually via a custom resource agent that communicates +with the provider's APIs) and maintaining a static IP address between reboots, +as well as resource contention issues. + +== Virtual Machines as Remote Nodes == + +Virtual machines may be configured following the process for remote nodes +rather than guest nodes (i.e., using an *ocf:pacemaker:remote* resource +rather than letting the cluster manage the VM directly). + +This is mainly useful in testing, to use a single physical host to simulate a +larger cluster involving remote nodes. Pacemaker's Cluster Test Suite (CTS) +uses this approach to test remote node functionality. + +== Containers as Guest Nodes == + +Containers,footnote:[https://en.wikipedia.org/wiki/Operating-system-level_virtualization] +and in particular Linux containers (LXC) and Docker, have become a popular +method of isolating services in a resource-efficient manner. + +The preferred means of integrating containers into Pacemaker is as a +cluster resource, whether opaque or using Pacemaker's built-in +resource isolation support.footnote:[Documentation for this support is planned +but not yet available.] + +However, it is possible to run `pacemaker_remote` inside a container, +following the process for guest nodes. This is not recommended but can +be useful, for example, in testing scenarios, to simulate a large number of +guest nodes. + +The configuration process is very similar to that described for guest nodes +using virtual machines. Key differences: + +* The underlying host must install the libvirt driver for the desired container + technology -- for example, the +libvirt-daemon-lxc+ package to get the + http://libvirt.org/drvlxc.html:[libvirt-lxc] driver for LXC containers. + +* Libvirt XML definitions must be generated for the containers. The + +pacemaker-cts+ package includes a helpful script for this purpose, + +/usr/share/pacemaker/tests/cts/lxc_autogen.sh+. Run it with the + `--help` option for details on how to use it. Of course, you can create + XML definitions manually, following the appropriate libvirt driver + documentation. + +* To share the authentication key, either share the host's +/etc/pacemaker+ + directory with the container, or copy the key into the container's + filesystem. + +* The *VirtualDomain* resource for a container will need + *force_stop="true"* and an appropriate hypervisor option, + for example *hypervisor="lxc:///"* for LXC containers. diff --git a/doc/Pacemaker_Remote/en-US/Ch-Baremetal-Tutorial.txt b/doc/Pacemaker_Remote/en-US/Ch-Baremetal-Tutorial.txt index d0fd14b02f..c187b2536f 100644 --- a/doc/Pacemaker_Remote/en-US/Ch-Baremetal-Tutorial.txt +++ b/doc/Pacemaker_Remote/en-US/Ch-Baremetal-Tutorial.txt @@ -1,230 +1,306 @@ -= Baremetal Walk-through = += Remote Node Walk-through = -+What this tutorial is:+ This tutorial is an in-depth walk-through of how to get pacemaker to integrate a baremetal remote-node into the cluster as a node capable of running cluster resources. +*What this tutorial is:* An in-depth walk-through of how to get Pacemaker to +integrate a remote node into the cluster as a node capable of running cluster +resources. -+What this tutorial is not:+ This tutorial is not a realistic deployment scenario. The steps shown here are meant to get users familiar with the concept of remote-nodes as quickly as possible. +*What this tutorial is not:* A realistic deployment scenario. The steps shown +here are meant to get users familiar with the concept of remote nodes as +quickly as possible. -This tutorial requires three machines. Two machines to act as cluster-nodes and a third to act as the baremetal remote-node. +This tutorial requires three machines: two to act as cluster nodes, and +a third to act as the remote node. -This tutorial was tested using Fedora 20 on both the cluster-nodes and baremetal remote-node. Anything that is capable of running pacemaker v1.1.11 or greater will do though. An installation guide for installing Fedora 20 can be found here, http://docs.fedoraproject.org/en-US/Fedora/20/html/Installation_Guide/. +== Configure Remote Node == -Fedora 20 (or similar distro) host preparation steps. +=== Configure Firewall on Remote Node === -== SElinux and Firewall Considerations == -In order to simply this tutorial we will disable selinux and the firewall on all the nodes. -+WARNING:+ These actions will open a significant security threat to machines exposed to the outside world. -[source,C] +Allow cluster-related services through the local firewall: +---- +# firewall-cmd --permanent --add-service=high-availability +success +# firewall-cmd --reload +success +---- + +[NOTE] +====== +If you are using iptables directly, or some other firewall solution besides +firewalld, simply open the following ports, which can be used by various +clustering components: TCP ports 2224, 3121, and 21064, and UDP port 5405. + +If you run into any problems during testing, you might want to disable +the firewall and SELinux entirely until you have everything working. +This may create significant security issues and should not be performed on +machines that will be exposed to the outside world, but may be appropriate +during development and testing on a protected host. + +To disable security measures: ---- # setenforce 0 # sed -i.bak "s/SELINUX=enforcing/SELINUX=permissive/g" /etc/selinux/config -# firewall-cmd --add-port 3121/tcp --permanent -# systemctl disable iptables.service -# systemctl disable ip6tables.service -# rm '/etc/systemd/system/basic.target.wants/iptables.service' -# rm '/etc/systemd/system/basic.target.wants/ip6tables.service' -# systemctl stop iptables.service -# systemctl stop ip6tables.service +# systemctl disable firewalld.service +# systemctl stop firewalld.service +# iptables --flush ---- +====== -== Setup Pacemaker Remote on Baremetal remote-node == +=== Configure pacemaker_remote on Remote Node === -On the baremetal remote-node machine run these commands to generate an authkey and copy it to the /etc/pacemaker folder. - -[source,C] +Install the pacemaker_remote daemon on the remote node. ---- -# mkdir /etc/pacemaker -# dd if=/dev/urandom of=/etc/pacemaker/authkey bs=4096 count=1 +# yum install -y pacemaker-remote resource-agents pcs ---- -Make sure to distribute this key to both of the cluster-nodes as well. All the nodes must have the same /etc/pacemaker/authkey installed for the communication to work correctly. +Create a location for the shared authentication key: +---- +# mkdir -p --mode=0750 /etc/pacemaker +# chgrp haclient /etc/pacemaker +---- -Now install and start the pacemaker_remote daemon on the baremetal remote-node. +All nodes (both cluster nodes and remote nodes) must have the same +authentication key installed for the communication to work correctly. +If you already have a key on an existing node, copy it to the new +remote node. Otherwise, create a new key, for example: +---- +# dd if=/dev/urandom of=/etc/pacemaker/authkey bs=4096 count=1 +---- -[source,C] +Now start and enable the pacemaker_remote daemon on the remote node. ---- -# yum install -y pacemaker-remote resource-agents pcs # systemctl enable pacemaker_remote.service # systemctl start pacemaker_remote.service ---- Verify the start is successful. -[source,C] ---- # systemctl status pacemaker_remote +pacemaker_remote.service - Pacemaker Remote Service + Loaded: loaded (/usr/lib/systemd/system/pacemaker_remote.service; enabled) + Active: active (running) since Fri 2015-08-21 15:21:20 CDT; 20s ago + Main PID: 21273 (pacemaker_remot) + CGroup: /system.slice/pacemaker_remote.service + └─21273 /usr/sbin/pacemaker_remoted - pacemaker_remote.service - Pacemaker Remote Service - Loaded: loaded (/usr/lib/systemd/system/pacemaker_remote.service; enabled) - Active: active (running) since Thu 2013-03-14 18:24:04 EDT; 2min 8s ago - Main PID: 1233 (pacemaker_remot) - CGroup: name=systemd:/system/pacemaker_remote.service - └─1233 /usr/sbin/pacemaker_remoted - - Mar 14 18:24:04 remote1 systemd[1]: Starting Pacemaker Remote Service... - Mar 14 18:24:04 remote1 systemd[1]: Started Pacemaker Remote Service. - Mar 14 18:24:04 remote1 pacemaker_remoted[1233]: notice: lrmd_init_remote_tls_server: Starting a tls listener on port 3121. +Aug 21 15:21:20 remote1 systemd[1]: Starting Pacemaker Remote Service... +Aug 21 15:21:20 remote1 systemd[1]: Started Pacemaker Remote Service. +Aug 21 15:21:20 remote1 pacemaker_remoted[21273]: notice: crm_add_logfile: Additional logging available in /var/log/pacemaker.log +Aug 21 15:21:20 remote1 pacemaker_remoted[21273]: notice: lrmd_init_remote_tls_server: Starting a tls listener on port 3121. +Aug 21 15:21:20 remote1 pacemaker_remoted[21273]: notice: bind_and_listen: Listening on address :: ---- -== Verify cluster-node Connection to baremetal-node == +== Verify Connection to Remote Node == -Before moving forward it's worth going ahead and verifying the cluster-nodes can contact the baremetal node on port 3121. Here's a trick you can use. Connect using telnet from each of the cluster-nodes. The connection will get destroyed, but how it is destroyed tells you whether it worked or not. +Before moving forward, it's worth verifying that the cluster nodes +can contact the remote node on port 3121. Here's a trick you can use. +Connect using ssh from each of the cluster nodes. The connection will get +destroyed, but how it is destroyed tells you whether it worked or not. -First add the baremetal remote-node's hostname (we're using remote1 in this tutorial) to the cluster-nodes' /etc/hosts files if you haven't already. This is required unless you have dns setup in a way where remote1's address can be discovered. +First, add the remote node's hostname (we're using *remote1* in this tutorial) +to the cluster nodes' +/etc/hosts+ files if you haven't already. This +is required unless you have DNS set up in a way where remote1's address can be +discovered. -Execute the following on each cluster-node, replacing the ip address with the actual ip address of the baremetal remote-node. -[source,C] +Execute the following on each cluster node, replacing the IP address with the +actual IP address of the remote node. ---- # cat << END >> /etc/hosts -192.168.122.10 remote1 +192.168.122.10 remote1 END ---- -If running the telnet command on one of the cluster-nodes results in this output before disconnecting, the connection works. -[source,C] +If running the ssh command on one of the cluster nodes results in this +output before disconnecting, the connection works. ---- -# telnet remote1 3121 - Trying 192.168.122.10... - Connected to remote1. - Escape character is '^]'. - Connection closed by foreign host. +# ssh -p 3121 remote1 +ssh_exchange_identification: read: Connection reset by peer ---- If you see this, the connection is not working. -[source,C] ---- -# telnet remote1 3121 -Trying 192.168.122.10... -telnet: connect to address 192.168.122.10: No route to host +# ssh -p 3121 remote1 +ssh: connect to host remote1 port 3121: No route to host ---- -Once you can successfully connect to the baremetal remote-node from the both cluster-nodes, move on to setting up pacemaker on the cluster-nodes. +Once you can successfully connect to the remote node from the both +cluster nodes, move on to setting up Pacemaker on the cluster nodes. + +== Configure Cluster Nodes == + +=== Configure Firewall on Cluster Nodes === -== Install cluster-node Software == +On each cluster node, allow cluster-related services through the local +firewall, following the same procedure as in <<_configure_firewall_on_remote_node>>. -On the two cluster-nodes install the following packages. +=== Install Pacemaker on Cluster Nodes === + +On the two cluster nodes, install the following packages. -[source,C] ---- # yum install -y pacemaker corosync pcs resource-agents ---- -== Setup Corosync on cluster-nodes == - -Corosync handles pacemaker's cluster membership and messaging. The corosync config file is located in /etc/corosync/corosync.conf. That config file must be initialized with information about the two cluster-nodes before pacemaker can start. +=== Copy Authentication Key to Cluster Nodes === -To initialize the corosync config file, execute the following pcs command on both nodes filling in the information in <> with your nodes' information. -[source,C] +Create a location for the shared authentication key, +and copy it from any existing node: ---- -# pcs cluster setup --local mycluster +# mkdir -p --mode=0750 /etc/pacemaker +# chgrp haclient /etc/pacemaker +# scp remote1:/etc/pacemaker/authkey /etc/pacemaker/authkey ---- -A recent syntax change in pcs may cause the above command to fail. If so try this alternative. -[source,C] +=== Configure Corosync on Cluster Nodes === + +Corosync handles Pacemaker's cluster membership and messaging. The corosync +config file is located in +/etc/corosync/corosync.conf+. That config file must be +initialized with information about the two cluster nodes before pacemaker can +start. + +To initialize the corosync config file, execute the following pcs command on +both nodes, filling in the information in <> with your nodes' information. ---- # pcs cluster setup --force --local --name mycluster ---- -== Start Pacemaker on cluster-nodes == +=== Start Pacemaker on Cluster Nodes === Start the cluster stack on both cluster nodes using the following command. -[source,C] ---- # pcs cluster start ---- Verify corosync membership -[source,C] ----- +.... # pcs status corosync - Membership information +---------------------- Nodeid Votes Name -1795270848 1 node1 (local) ----- + 1 1 node1 (local) +.... -Verify pacemaker status. At first the 'pcs cluster status' output will look like this. +Verify Pacemaker status. At first, the `pcs cluster status` output will look +like this. -[source,C] ---- # pcs status - - Last updated: Thu Mar 14 12:26:00 2013 - Last change: Thu Mar 14 12:25:55 2013 via crmd on example-host - Stack: corosync - Current DC: - Version: 1.1.11 - 1 Nodes configured, unknown expected votes - 0 Resources configured. +Cluster name: mycluster +Last updated: Fri Aug 21 16:14:05 2015 +Last change: Fri Aug 21 14:02:14 2015 +Stack: corosync +Current DC: NONE +Version: 1.1.12-a14efad +1 Nodes configured, unknown expected votes +0 Resources configured ---- -After about a minute you should see your two cluster-nodes come online. +After about a minute, you should see your two cluster nodes come online. -[source,C] ---- # pcs status +Cluster name: mycluster +Last updated: Fri Aug 21 16:16:32 2015 +Last change: Fri Aug 21 14:02:14 2015 +Stack: corosync +Current DC: node1 (1) - partition with quorum +Version: 1.1.12-a14efad +2 Nodes configured +0 Resources configured - Last updated: Thu Mar 14 12:28:23 2013 - Last change: Thu Mar 14 12:25:55 2013 via crmd on node1 - Stack: corosync - Current DC: node1 (1795270848) - partition with quorum - Version: 1.1.11 - 2 Nodes configured, unknown expected votes - 0 Resources configured. - - Online: [ node1 node2 ] +Online: [ node1 node2 ] ---- For the sake of this tutorial, we are going to disable stonith to avoid having to cover fencing device configuration. -[source,C] ---- # pcs property set stonith-enabled=false ---- -== Integrate Baremetal remote-node into Cluster == +== Integrate Remote Node into Cluster == -Integrating a baremetal remote-node into the cluster is achieved through the creation of a remote-node connection resource. The remote-node connection resource both establishes the connection to the remote-node and defines that the remote-node exists. Note that this resource is actually internal to Pacemaker's crmd component. A metadata file for this resource can be found in the /usr/lib/ocf/resource.d/pacemaker/remote file that describes what options are available, but there is no actual ocf:pacemaker:remote resource agent script that performs any work. +Integrating a remote node into the cluster is achieved through the +creation of a remote node connection resource. The remote node connection +resource both establishes the connection to the remote node and defines that +the remote node exists. Note that this resource is actually internal to +Pacemaker's crmd component. A metadata file for this resource can be found in +the +/usr/lib/ocf/resource.d/pacemaker/remote+ file that describes what options +are available, but there is no actual *ocf:pacemaker:remote* resource agent +script that performs any work. -Define the remote-node connection resource to our baremetal remote-node, remote1, using the following command. +Define the remote node connection resource to our remote node, +*remote1*, using the following command on any cluster node. -[source,C] ---- # pcs resource create remote1 ocf:pacemaker:remote ---- -That's it. After a moment you should see the remote-node come online. +That's it. After a moment you should see the remote node come online. -[source,C] ---- -Last updated: Fri Oct 18 18:47:21 2013 -Last change: Fri Oct 18 18:46:14 2013 via cibadmin on node1 +Cluster name: mycluster +Last updated: Fri Aug 21 17:13:09 2015 +Last change: Fri Aug 21 17:02:02 2015 Stack: corosync -Current DC: node1 (1) - partition with quorum -Version: 1.1.11 +Current DC: node1 (1) - partition with quorum +Version: 1.1.12-a14efad 3 Nodes configured 1 Resources configured + Online: [ node1 node2 ] RemoteOnline: [ remote1 ] -remote1 (ocf::pacemaker:remote): Started node1 +Full list of resources: + + remote1 (ocf::pacemaker:remote): Started node1 + +PCSD Status: + node1: Online + node2: Online + +Daemon Status: + corosync: active/disabled + pacemaker: active/disabled + pcsd: active/enabled ---- -== Starting Resources on baremetal remote-node == +== Starting Resources on Remote Node == + +Once the remote node is integrated into the cluster, starting resources on a +remote node is the exact same as on cluster nodes. Refer to the +http://clusterlabs.org/doc/['Clusters from Scratch'] document for examples of +resource creation. -+"Warning: Never involve a remote-node connection resource in a resource group, colocation, or order constraint"+ +[WARNING] +========= +Never involve a remote node connection resource in a resource group, +colocation constraint, or order constraint. +========= -Once the baremetal remote-node is integrated into the cluster, starting resources on a baremetal remote-node is the exact same as the cluster nodes. Refer to the Clusters from Scratch document for examples on resource creation. http://clusterlabs.org/doc/ +== Fencing Remote Nodes == -== Fencing baremetal remote-nodes == +Remote nodes are fenced the same way as cluster nodes. No special +considerations are required. Configure fencing resources for use with +remote nodes the same as you would with cluster nodes. -The cluster understands how to fence baremetal remote-nodes and can use standard fencing devices to do so. No special considerations are required. Note however that remote-nodes can never initiate a fencing action. Only cluster-nodes are capable of actually executing the fencing operation on another node. +Note, however, that remote nodes can never 'initiate' a fencing action. Only +cluster nodes are capable of actually executing a fencing operation against +another node. -== Accessing Cluster Tools from a Baremetal remote-node == +== Accessing Cluster Tools from a Remote Node == -Besides allowing the cluster to manage resources on a remote-node, pacemaker_remote has one other trick. +The pacemaker_remote daemon allows nearly all the pacemaker tools (crm_resource, crm_mon, crm_attribute, crm_master) to work on remote nodes natively.+ +Besides allowing the cluster to manage resources on a remote node, +pacemaker_remote has one other trick. The pacemaker_remote daemon allows +nearly all the pacemaker tools (`crm_resource`, `crm_mon`, `crm_attribute`, +`crm_master`, etc.) to work on remote nodes natively. -Try it, run +crm_mon+ or +pcs status+ on the baremetal node after pacemaker has integrated the remote-node into the cluster. These tools just work. These means resource agents such as master/slave resources which need access to tools like crm_master work seamlessly on the remote-nodes. +Try it: Run `crm_mon` on the remote node after pacemaker has +integrated it into the cluster. These tools just work. These means resource +agents such as master/slave resources which need access to tools like +`crm_master` work seamlessly on the remote nodes. +Higher-level command shells such as `pcs` may have partial support +on remote nodes, but it is recommended to run them from a cluster node. diff --git a/doc/Pacemaker_Remote/en-US/Ch-Example.txt b/doc/Pacemaker_Remote/en-US/Ch-Example.txt index 5db250f551..9513e3da6a 100644 --- a/doc/Pacemaker_Remote/en-US/Ch-Example.txt +++ b/doc/Pacemaker_Remote/en-US/Ch-Example.txt @@ -1,107 +1,130 @@ -= KVM Remote-node Quick Example = - -If you already know how to use pacemaker, you'll likely be able to grasp this new concept of remote-nodes by reading through this quick example without having to sort through all the detailed walk-through steps. Here are the key configuration ingredients that make this possible using libvirt and KVM virtual guests. These steps strip everything down to the very basics. - -== Mile High View of Configuration Steps == - -* +Put an authkey with this path, /etc/pacemaker/authkey, on every cluster-node and virtual machine+. This secures remote communication and authentication. - -Run this command if you want to make a somewhat random authkey. - -[source,C] += Guest Node Quick Example = + +If you already know how to use Pacemaker, you'll likely be able to grasp this +new concept of guest nodes by reading through this quick example without +having to sort through all the detailed walk-through steps. Here are the key +configuration ingredients that make this possible using libvirt and KVM virtual +guests. These steps strip everything down to the very basics. +(((guest node))) +(((node,guest node))) + +== Mile-High View of Configuration Steps == + +* Give each virtual machine that will be used as a guest node a static network + address and unique hostname. + +* Put the same authentication key with the path +/etc/pacemaker/authkey+ on + every cluster node and virtual machine. This secures remote communication. ++ +Run this command if you want to make a somewhat random key: ++ ---- dd if=/dev/urandom of=/etc/pacemaker/authkey bs=4096 count=1 ---- -* +Install pacemaker_remote packages on every virtual machine, enable pacemaker_remote on startup, and poke hole in firewall for tcp port 3121.+ - -[source,C] +* Install pacemaker_remote on every virtual machine, enabling it to start at + boot, and if a local firewall is used, allow the node to accept connections + on TCP port 3121. ++ ---- yum install pacemaker-remote resource-agents systemctl enable pacemaker_remote -# If you just want to see this work, disable iptables and ip6tables on most distros. -# You may have to put selinux in permissive mode as well for the time being. firewall-cmd --add-port 3121/tcp --permanent ---- - -* +Give each virtual machine a static network address and unique hostname+ - -* +Tell pacemaker to launch a virtual machine and that the virtual machine is a remote-node capable of running resources by using the "remote-node" meta-attribute.+ - -with pcs - -[source,C] ++ +[NOTE] +====== +If you just want to see this work, you may want to simply disable the local +firewall and put SELinux in permissive mode while testing. This creates +security risks and should not be done on a production machine exposed to the +Internet, but can be appropriate for a protected test machine. +====== + +* Create a Pacemaker resource to launch each virtual machine, using the + *remote-node* meta-attribute to let Pacemaker know this will be a + guest node capable of running resources. ++ ---- -# pcs resource create vm-guest1 VirtualDomain hypervisor="qemu:///system" config="vm-guest1.xml" meta +remote-node=guest1+ +# pcs resource create vm-guest1 VirtualDomain hypervisor="qemu:///system" config="vm-guest1.xml" meta remote-node="guest1" ---- - -raw xml ++ +The above command will create CIB XML similar to the following: ++ [source,XML] ---- ---- -In the example above the meta-attribute 'remote-node=guest1' tells pacemaker that this resource is a remote-node with the hostname 'guest1' that is capable of being integrated into the cluster. The cluster will attempt to contact the virtual machine's pacemaker_remote service at the hostname 'guest1' after it launches. +In the example above, the meta-attribute *remote-node="guest1"* tells Pacemaker +that this resource is a guest node with the hostname *guest1*. The cluster will +attempt to contact the virtual machine's pacemaker_remote service at the +hostname *guest1* after it launches. -== What those steps just did == +[NOTE] +====== +The ID of the resource creating the virtual machine (*vm-guest1* in the above +example) 'must' be different from the virtual machine's uname (*guest1* in the +above example). Pacemaker will create an implicit internal resource for the +pacemaker_remote connection to the guest, named with the value of *remote-node*, +so that value cannot be used as the name of any other resource. +====== -Those steps just told pacemaker to launch a virtual machine called vm-guest1 and integrate that virtual machine as a remote-node called 'guest1'. +== Using a Guest Node == -Example crm_mon output after guest1 is integrated into cluster. +Guest nodes will show up in `crm_mon` output as normal: -[source,C] +.Example `crm_mon` output after *guest1* is integrated into cluster ---- Last updated: Wed Mar 13 13:52:39 2013 Last change: Wed Mar 13 13:25:17 2013 via crmd on node1 Stack: corosync Current DC: node1 (24815808) - partition with quorum Version: 1.1.10 2 Nodes configured, unknown expected votes 2 Resources configured. Online: [ node1 guest1] vm-guest1 (ocf::heartbeat:VirtualDomain): Started node1 ---- -Now, you could place a resource, such as a webserver on guest1. - -[source,C] +Now, you could place a resource, such as a webserver, on *guest1*: ---- # pcs resource create webserver apache params configfile=/etc/httpd/conf/httpd.conf op monitor interval=30s # pcs constraint webserver prefers guest1 ---- -Now the crm_mon output would show a webserver launched on the guest1 remote-node. - -[source,C] +Now, the crm_mon output would show: ---- Last updated: Wed Mar 13 13:52:39 2013 Last change: Wed Mar 13 13:25:17 2013 via crmd on node1 Stack: corosync Current DC: node1 (24815808) - partition with quorum Version: 1.1.10 2 Nodes configured, unknown expected votes 2 Resources configured. Online: [ node1 guest1] vm-guest1 (ocf::heartbeat:VirtualDomain): Started node1 webserver (ocf::heartbeat::apache): Started guest1 ---- -== Accessing Cluster from Remote-node == - -It is worth noting that after 'guest1' is integrated into the cluster, all the pacemaker cli tools immediately become available to the remote node. This means things like crm_mon, crm_resource, and crm_attribute will work natively on the remote-node as long as the connection between the remote-node and cluster-node exists. This is particularly important for any master/slave resources executing on the remote-node that need access to crm_master to set the nodes transient attributes. - +It is worth noting that after *guest1* is integrated into the cluster, nearly all the +Pacemaker command-line tools immediately become available to the guest node. +This means things like `crm_mon`, `crm_resource`, and `crm_attribute` will work +natively on the guest node, as long as the connection between the guest node +and a cluster node exists. This is particularly important for any master/slave +resources executing on the guest node that need access to `crm_master` to set +transient attributes. diff --git a/doc/Pacemaker_Remote/en-US/Ch-Future.txt b/doc/Pacemaker_Remote/en-US/Ch-Future.txt deleted file mode 100644 index 43d136c4e8..0000000000 --- a/doc/Pacemaker_Remote/en-US/Ch-Future.txt +++ /dev/null @@ -1,17 +0,0 @@ -= Future Features = - -Basic KVM and Linux container integration was the first phase of development for pacemaker_remote and was completed for Pacemaker v1.1.10. Here are some planned features that expand upon this initial functionality. - -== Libvirt Sandbox Support == - -Once the libvirt-sandbox project is integrated with pacemaker_remote, we will gain the ability to preform per-resource linux container isolation with very little performance impact. This functionality will allow resources living on a single node to be isolated from one another. At that point CPU and memory limits could be set per-resource dynamically just using the cluster config. - -== Bare-metal Support == -+"This feature has already been introduced into Pacemaker's master github branch and is scheduled for Pacemaker v1.1.11"+ - -The pacemaker_remote daemon already has the ability to run on bare-metal hardware nodes, but the policy engine logic for integrating bare-metal nodes is not complete. There are some complications involved with understanding a bare-metal node's state that virtual nodes don't have. Once this logic is complete, pacemaker will be able to integrate bare-metal nodes in the same way virtual remote-nodes currently are. Some special considerations for fencing will need to be addressed. - -== KVM Migration Support == -+"This feature has already been introduced into Pacemaker's master github branch and is scheduled for Pacemaker v1.1.12"+ - -Pacemaker's policy engine is limited in its ability to perform live migrations of KVM resources when resource dependencies are involved. This limitation affects how resources living within a KVM remote-node are handled when a live migration takes place. Currently when a live migration is performed on a KVM remote-node, all the resources within that remote-node have to be stopped before the migration takes place and started once again after migration has finished. This policy engine limitation is fully explained in this bug report, http://bugs.clusterlabs.org/show_bug.cgi?id=5055#c3 diff --git a/doc/Pacemaker_Remote/en-US/Ch-Intro.txt b/doc/Pacemaker_Remote/en-US/Ch-Intro.txt index 777bb976a1..438ecd2aa4 100644 --- a/doc/Pacemaker_Remote/en-US/Ch-Intro.txt +++ b/doc/Pacemaker_Remote/en-US/Ch-Intro.txt @@ -1,85 +1,193 @@ -= Extending High Availability Cluster into Virtual Nodes = += Scaling a Pacemaker Cluster = == Overview == -The recent addition of the +pacemaker_remote+ service supported by +Pacemaker version 1.1.10 and greater+ allows nodes not running the cluster stack (pacemaker+corosync) to integrate into the cluster and have the cluster manage their resources just as if they were a real cluster node. This means that pacemaker clusters are now capable of managing both launching virtual environments (KVM/LXC) as well as launching the resources that live within those virtual environments without requiring the virtual environments to run pacemaker or corosync. +In a basic Pacemaker high-availability +cluster,footnote:[See the http://www.clusterlabs.org/doc/[Pacemaker +documentation], especially 'Clusters From Scratch' and 'Pacemaker Explained', +for basic information about high-availability using Pacemaker] +each node runs the full cluster stack of corosync and all Pacemaker components. +This allows great flexibility but limits scalability to around 16 nodes. -== Terms == -+cluster-node+ - A node running the High Availability stack (pacemaker + corosync) - -+remote-node+ - A node running pacemaker_remote without the rest of the High Availability stack. There are two types of remote-nodes, container and baremetal. - -+container+ - A pacemaker resource that contains additional resources. For example, a KVM virtual machine resource that contains a webserver resource. - -+container remote-node+ - A virtual guest remote-node running the pacemaker_remote service. This describes a specific remote-node use case where a virtual guest resource managed by the cluster is both started by the cluster and integrated into the cluster as a remote-node. - -+baremetal+ - Term used to describe an environment that is not virtualized. - -+baremetal remote-node+ - A baremetal hardware node running pacemaker_remote. This describes a specific remote-node use case where a hardware node not running the High Availability stack is integrated into the cluster as a remote-node through the use of pacemaker_remote. - -+pacemaker_remote+ - A service daemon capable of performing remote application management within guest nodes (baremetal, kvm, and lxc) in both pacemaker cluster environments and standalone (non-cluster) environments. This service is an enhanced version of pacemaker's local resource manage daemon (LRMD) that is capable of managing and monitoring LSB, OCF, upstart, and systemd resources on a guest remotely. It also allows for most of pacemaker's cli tools (crm_mon, crm_resource, crm_master, crm_attribute, ect..) to work natively on remote-nodes. - -+LXC+ - A Linux Container defined by the libvirt-lxc Linux container driver. http://libvirt.org/drvlxc.html - -== Version Info == - -This feature is in ongoing development. - -+Pacemaker v1.1.10+ - -* Initial pacemaker_remote daemon and integration support. -* Only supports pacemaker in KVM/LXC environments. -* pacemaker_remote daemon unit test suite. -* Known bugs include (These are likely resolved if you have received an 1.1.10.x point release): Errors when setting remote-node attributes, Failures when stopping orphaned (deleted from cib while running) remote-nodes, Fixes remote-node usage in asymmetric clusters. - -+Currently in Master github branch and scheduled for Pacemaker v1.1.11+ - -* Baremetal remote-node support. -* Improvements to scaling remote-node integration. Performance testing here included 16 cluster nodes running 64 remote-nodes living in LXC containers. As part of this testing, several performance enhancements were introduced into the integration code. -* CTS tests. RemoteLXC and RemoteBaremetal. These two CTS tests allow us to perform automated verification of pacemaker_remote integration. -* Fixes for known bugs in 1.1.10 release. - -== Virtual Machine Use Case == -The use of pacemaker_remote in virtual machines solves a deployment scenario that has traditionally been difficult to solve. +To allow for scalability to dozens or even hundreds of nodes, Pacemaker +allows nodes not running the full cluster stack to integrate into the cluster +and have the cluster manage their resources as if they were a cluster node. -+"I want a pacemaker cluster to manage virtual machine resources, but I also want pacemaker to be able to manage the resources that live within those virtual machines."+ - -In the past, users desiring this deployment had to make a decision. They would either have to sacrifice the ability of monitoring resources residing within virtual guests by running the cluster stack on the baremetal nodes, or run another cluster instance on the virtual guests where they potentially run into corosync scalability issues. There is a third scenario where the virtual guests run the cluster stack and join the same network as the baremetal nodes, but that can quickly hit issues with scalability as well. - -With the pacemaker_remote service we have a new option. - -* The baremetal cluster-nodes run the cluster stack (pacemaker+corosync). -* The virtual remote-nodes run the pacemaker_remote service (nearly zero configuration required on the virtual machine side) -* The cluster stack on the cluster-nodes launch the virtual machines and immediately connect to the pacemaker_remote service, allowing the virtual machines to integrate into the cluster just as if they were a real cluster-node. - -The key difference here between the virtual machine remote-nodes and the cluster-nodes is that the remote-nodes are not running the cluster stack. This means the remote nodes will never become the DC, and they do not take place in quorum. On the other hand this also means that remote-nodes are not bound to the scalability limits associated with the cluster stack either. +No 16 node corosync member limits+ to deal with. That isn't to say remote-nodes can scale indefinitely, but it is known that remote-nodes scale horizontally much further than cluster-nodes. Other than the quorum limitation, these remote-nodes behave just like cluster nodes in respects to resource management. The cluster is fully capable of managing and monitoring resources on each remote-node. You can build constraints against remote-nodes, put them in standby, or whatever else you'd expect to be able to do with normal cluster-nodes. They even show up in the crm_mon output as you would expect cluster-nodes to. - -To solidify the concept, below is an example deployment that is very similar to an actual deployment we test in our developer environment to verify remote-node scalability. - -* 16 cluster-nodes running corosync+pacemaker stack. -* 64 pacemaker managed virtual machine resources running pacemaker_remote configured as remote-nodes. -* 64 pacemaker managed webserver and database resources configured to run on the 64 remote-nodes. - -With this deployment you would have 64 webservers and databases running on 64 virtual machines on 16 hardware nodes all of which are managed and monitored by the same pacemaker deployment. It is known that pacemaker_remote can scale to these lengths and possibly much further depending on the specific scenario. - -== Baremetal remote-node Use Case == - -+"I want my traditional High Availability cluster to scale beyond the limits imposed by the corosync messaging layer."+ - -Ultimately the primary advantage of baremetal remote-nodes over traditional nodes running the Corosync+Pacemaker stack is scalability. There are likely some other use cases related to geographically distributed HA clusters that baremetal remote-nodes may serve a purpose in, but those use cases are not well understood at this point. The only limitations baremetal remote-nodes have that cluster-nodes do not is the ability to take place in cluster quorum, and the ability to execute fencing agents via stonith. That is not to say however that fencing of a baremetal node works any differently than that of a normal cluster-node. The Pacemaker policy engine understands how to fence baremetal remote-nodes. As long as a fencing device exists, the cluster is capable of ensuring baremetal nodes are fenced in the exact same way as normal cluster-nodes are fenced. - -== Linux Container Use Case == - -+I want to isolate and limit the system resources (cpu, memory, filesystem) a cluster resource can consume without using virtual machines.+ +== Terms == -Using pacemaker_remote with Linux containers (libvirt-lxc) opens up some interesting possibilities for isolating resources in the cluster without the use of a hypervisor. We now have the ability to both define a contained environment with cpu and memory utilization limits and then assign resources to that contained environment all managed from within pacemaker. The LXC Walk-through section of this document outlines how pacemaker_remote can be used to bring Linux containers into the cluster as remote-nodes capable of executing resources. +cluster node:: + A node running the full high-availability stack of corosync and all + Pacemaker components. Cluster nodes may run cluster resources, run + all Pacemaker command-line tools (`crm_mon`, `crm_resource` and so on), + execute fencing actions, count toward cluster quorum, and serve as the + cluster's Designated Controller (DC). +(((cluster node))) +(((node,cluster node))) + +pacemaker_remote:: + A small service daemon that allows a host to be used as a Pacemaker node + without running the full cluster stack. Nodes running pacemaker_remote + may run cluster resources and most command-line tools, but cannot perform + other functions of full cluster nodes such as fencing execution, quorum + voting or DC eligibility. The pacemaker_remote daemon is an enhanced + version of Pacemaker's local resource management daemon (LRMD). +(((pacemaker_remote))) + +remote node:: + A physical host running pacemaker_remote. Remote nodes have a special + resource that manages communication with the cluster. This is sometimes + referred to as the 'baremetal' case. +(((remote node))) +(((node,remote node))) + +guest node:: + A virtual host running pacemaker_remote. Guest nodes differ from remote + nodes mainly in that the guest node is itself a resource that the cluster + manages. +(((guest node))) +(((node,guest node))) + +[NOTE] +====== +'Remote' in this document refers to the node not being a part of the underlying +corosync cluster. It has nothing to do with physical proximity. Remote nodes +and guest nodes are subject to the same latency requirements as cluster nodes, +which means they are typically in the same data center. +====== + +[NOTE] +====== +It is important to distinguish the various roles a virtual machine can serve +in Pacemaker clusters: + +* A virtual machine can run the full cluster stack, in which case it is a + cluster node and is not itself managed by the cluster. +* A virtual machine can be managed by the cluster as a resource, without the + cluster having any awareness of the services running inside the virtual + machine. The virtual machine is 'opaque' to the cluster. +* A virtual machine can be a cluster resource, and run pacemaker_remote + to make it a a guest node, allowing the cluster to manage services + inside it. The virtual machine is 'transparent' to the cluster. +====== + +== Support in Pacemaker Versions == + +It is recommended to run Pacemaker 1.1.12 or later when using pacemaker_remote +due to important bug fixes. An overview of changes in pacemaker_remote +capability by version: + +.1.1.13 +* Support for maintenance mode +* Remote nodes can recover without being fenced when the cluster node + hosting their connection fails +* Running pacemaker_remote within LXC environments is deprecated due to + newly added Pacemaker support for isolated resources +* Bug fixes + +.1.1.12 +* Support for permanent node attributes +* Support for migration +* Bug fixes + +.1.1.11 +* Support for IPv6 +* Support for remote nodes +* Support for transient node attributes +* Support for clusters with mixed endian architectures +* Bug fixes + +.1.1.10 +* Bug fixes + +.1.1.9 +* Initial version to include pacemaker_remote +* Limited to guest nodes in KVM/LXC environments using only IPv4; + all nodes' architectures must have same endianness + +== Guest Nodes == +(((guest node))) +(((node,guest node))) + +*"I want a Pacemaker cluster to manage virtual machine resources, but I also +want Pacemaker to be able to manage the resources that live within those +virtual machines."* + +Without pacemaker_remote, the possibilities for implementing the above use case +have significant limitations: + +* The cluster stack could be run on the physical hosts only, which loses the + ability to monitor resources within the guests. +* A separate cluster could be on the virtual guests, which quickly hits + scalability issues. +* The cluster stack could be run on the guests using the same cluster as the + physical hosts, which also hits scalability issues and complicates fencing. + +With pacemaker_remote: + +* The physical hosts are cluster nodes (running the full cluster stack). +* The virtual machines are guest nodes (running the pacemaker_remote service). + Nearly zero configuration is required on the virtual machine. +* The cluster stack on the cluster nodes launches the virtual machines and + immediately connects to the pacemaker_remote service on them, allowing the + virtual machines to integrate into the cluster. + +The key difference here between the guest nodes and the cluster nodes is that +the guest nodes do not run the cluster stack. This means they will never become +the DC, initiate fencing actions or participate in quorum voting. + +On the other hand, this also means that they are not bound to the scalability +limits associated with the cluster stack (no 16-node corosync member limits to +deal with). That isn't to say that guest nodes can scale indefinitely, but it +is known that guest nodes scale horizontally much further than cluster nodes. + +Other than the quorum limitation, these guest nodes behave just like cluster +nodes with respect to resource management. The cluster is fully capable of +managing and monitoring resources on each guest node. You can build constraints +against guest nodes, put them in standby, or do whatever else you'd expect to +be able to do with cluster nodes. They even show up in `crm_mon` output as +nodes. + +To solidify the concept, below is an example that is very similar to an actual +deployment we test in our developer environment to verify guest node scalability: + +* 16 cluster nodes running the full corosync + pacemaker stack +* 64 Pacemaker-managed virtual machine resources running pacemaker_remote configured as guest nodes +* 64 Pacemaker-managed webserver and database resources configured to run on the 64 guest nodes + +With this deployment, you would have 64 webservers and databases running on 64 +virtual machines on 16 hardware nodes, all of which are managed and monitored by +the same Pacemaker deployment. It is known that pacemaker_remote can scale to +these lengths and possibly much further depending on the specific scenario. + + +== Remote Nodes == +(((remote node))) +(((node,remote node))) + +*"I want my traditional high-availability cluster to scale beyond the limits +imposed by the corosync messaging layer."* + +Ultimately, the primary advantage of remote nodes over cluster nodes is +scalability. There are likely some other use cases related to geographically +distributed HA clusters that remote nodes may serve a purpose in, but those use +cases are not well understood at this point. + +Like guest nodes, remote nodes will never become the DC, initiate +fencing actions or participate in quorum voting. + +That is not to say, however, that fencing of a remote node works any +differently than that of a cluster node. The Pacemaker policy engine +understands how to fence remote nodes. As long as a fencing device exists, the +cluster is capable of ensuring remote nodes are fenced in the exact same way as +cluster nodes. == Expanding the Cluster Stack == -=== Traditional HA Stack === - -image::images/pcmk-ha-cluster-stack.png["The Traditional Pacemaker Corosync HA Stack.",width="17cm",height="9cm",align="center"] +With pacemaker_remote, the traditional view of the high-availability stack can +be expanded to include a new layer: -=== Remote-Node Enabled HA Stack Using Virtual guest nodes === +.Traditional HA Stack +image::images/pcmk-ha-cluster-stack.png["Traditional Pacemaker+Corosync Stack",width="17cm",height="9cm",align="center"] -image::images/pcmk-ha-remote-stack.png["Placing Pacemaker Remote into the Traditional HA Stack.",width="20cm",height="10cm",align="center"] +.HA Stack With Guest Nodes +image::images/pcmk-ha-remote-stack.png["Pacemaker+Corosync Stack With pacemaker_remote",width="20cm",height="10cm",align="center"] diff --git a/doc/Pacemaker_Remote/en-US/Ch-KVM-Tutorial.txt b/doc/Pacemaker_Remote/en-US/Ch-KVM-Tutorial.txt index 7b150aa5ef..328a52eb0f 100644 --- a/doc/Pacemaker_Remote/en-US/Ch-KVM-Tutorial.txt +++ b/doc/Pacemaker_Remote/en-US/Ch-KVM-Tutorial.txt @@ -1,467 +1,477 @@ -= KVM Walk-through = += Guest Node Walk-through = -+What this tutorial is:+ This tutorial is an in-depth walk-through of how to get pacemaker to manage a KVM guest instance and integrate that guest into the cluster as a remote-node. +*What this tutorial is:* An in-depth walk-through of how to get Pacemaker to +manage a KVM guest instance and integrate that guest into the cluster as a +guest node. -+What this tutorial is not:+ This tutorial is not a realistic deployment scenario. The steps shown here are meant to get users familiar with the concept of remote-nodes as quickly as possible. +*What this tutorial is not:* A realistic deployment scenario. The steps shown +here are meant to get users familiar with the concept of guest nodes as quickly +as possible. -== Step 1: Setup the Host == - -This tutorial was created using Fedora 20 on the host and guest nodes. Anything that is capable of running libvirt and pacemaker v1.1.10 or greater will do though. An installation guide for installing Fedora 20 can be found here, http://docs.fedoraproject.org/en-US/Fedora/20/html/Installation_Guide/. - -Fedora 20 (or similar distro) host preparation steps. +== Configure the Physical Host == === SElinux and Firewall === -In order to simply this tutorial we will disable the selinux and the firewall on the host. -+WARNING:+ These actions will open a significant security threat to machines exposed to the outside world. -[source,C] + +In order to simplify this tutorial, we will disable SELinux and the local +firewall on the host. This may create significant security issues and should +not be performed on machines that will be exposed to the outside world, but may +be appropriate during development and testing on a protected host. ---- # setenforce 0 # sed -i.bak "s/SELINUX=enforcing/SELINUX=permissive/g" /etc/selinux/config -# systemctl disable iptables.service -# systemctl disable ip6tables.service -# rm '/etc/systemd/system/basic.target.wants/iptables.service' -# rm '/etc/systemd/system/basic.target.wants/ip6tables.service' -# systemctl stop iptables.service -# systemctl stop ip6tables.service +# systemctl disable firewalld.service +# systemctl stop firewalld.service +# iptables --flush ---- === Install Cluster Software === -[source,C] ---- # yum install -y pacemaker corosync pcs resource-agents ---- -=== Setup Corosync === +=== Configure Corosync === -Corosync handles pacemaker's cluster membership and messaging. The corosync config file is located in /etc/corosync/corosync.conf. That config file must be initialized with information about the cluster-nodes before pacemaker can start. +Corosync handles pacemaker's cluster membership and messaging. The corosync +config file is located in /etc/corosync/corosync.conf. That config file must be +initialized with information about the cluster nodes before pacemaker can +start. To initialize the corosync config file, execute the following pcs command on both nodes filling in the information in <> with your nodes' information. -[source,C] ----- -# pcs cluster setup --local mycluster ----- - -A recent syntax change in pcs may cause the above command to fail. If so try this alternative. -[source,C] ---- # pcs cluster setup --force --local --name mycluster ---- === Verify Cluster Software === Start the cluster - -[source,C] ---- # pcs cluster start ---- Verify corosync membership - -[source,C] ---- # pcs status corosync Membership information Nodeid Votes Name 1795270848 1 example-host (local) ---- -Verify pacemaker status. At first the 'pcs cluster status' output will look like this. - -[source,C] +Verify pacemaker status. At first, the output will look like this: ---- # pcs status Last updated: Thu Mar 14 12:26:00 2013 Last change: Thu Mar 14 12:25:55 2013 via crmd on example-host Stack: corosync Current DC: Version: 1.1.10 1 Nodes configured, unknown expected votes 0 Resources configured. ---- After about a minute you should see your host as a single node in the cluster. -[source,C] ---- # pcs status Last updated: Thu Mar 14 12:28:23 2013 Last change: Thu Mar 14 12:25:55 2013 via crmd on example-host Stack: corosync Current DC: example-host (1795270848) - partition WITHOUT quorum Version: 1.1.8-9b13ea1 1 Nodes configured, unknown expected votes 0 Resources configured. Online: [ example-host ] ---- Go ahead and stop the cluster for now after verifying everything is in order. - -[source,C] ---- # pcs cluster stop ---- === Install Virtualization Software === -[source,C] ---- # yum install -y kvm libvirt qemu-system qemu-kvm bridge-utils virt-manager # systemctl enable libvirtd.service ---- reboot the host -== Step2: Create the KVM guest == +[NOTE] +====== +While KVM is used in this example, any virtualization platform with a Pacemaker +resource agent can be used to create a guest node. The resource agent needs +only to support usual commands (start, stop, etc.); Pacemaker implements the +*remote-node* meta-attribute, independent of the agent. +====== + +== Configure the KVM guest == -I am not going to outline the installation steps required to create a kvm guest. There are plenty of tutorials available elsewhere that do that. I recommend using a Fedora 18 or greater distro as your guest as that is what I am testing this tutorial with. +=== Create Guest === -=== Setup Guest Network === +I am not going to outline the installation steps required to create a KVM +guest. There are plenty of tutorials available elsewhere that do that. + +=== Configure Guest Network === Run the commands below to set up a static ip address (192.168.122.10) and hostname (guest1). -[source,C] ---- export remote_hostname=guest1 export remote_ip=192.168.122.10 export remote_gateway=192.168.122.1 yum remove -y NetworkManager rm -f /etc/hostname cat << END >> /etc/hostname $remote_hostname END hostname $remote_hostname cat << END >> /etc/sysconfig/network HOSTNAME=$remote_hostname GATEWAY=$remote_gateway END sed -i.bak "s/.*BOOTPROTO=.*/BOOTPROTO=none/g" /etc/sysconfig/network-scripts/ifcfg-eth0 cat << END >> /etc/sysconfig/network-scripts/ifcfg-eth0 IPADDR0=$remote_ip PREFIX0=24 GATEWAY0=$remote_gateway DNS1=$remote_gateway END systemctl restart network systemctl enable network.service systemctl enable sshd systemctl start sshd echo "checking connectivity" ping www.google.com ---- To simplify the tutorial we'll go ahead and disable selinux on the guest. We'll also need to poke a hole through the firewall on port 3121 (the default port for pacemaker_remote) so the host can contact the guest. -[source,C] ---- # setenforce 0 # sed -i.bak "s/SELINUX=enforcing/SELINUX=permissive/g" /etc/selinux/config # firewall-cmd --add-port 3121/tcp --permanent ---- -If you still encounter connection issues just disable iptables and ipv6tables on the guest like we did on the host to guarantee you'll be able to contact the guest from the host. +If you still encounter connection issues, just disable firewalld on the guest +like we did on the host, to guarantee you'll be able to contact the guest from +the host. At this point you should be able to ssh into the guest from the host. -=== Setup Pacemaker Remote === +=== Configure pacemaker_remote === -On the +HOST+ machine run these commands to generate an authkey and copy it to the /etc/pacemaker folder on both the host and guest. +On the 'host' machine, run these commands to generate an authkey and copy it to +the /etc/pacemaker folder on both the host and guest. -[source,C] ---- -# mkdir /etc/pacemaker +# mkdir -p --mode=0750 /etc/pacemaker +# chgrp haclient /etc/pacemaker # dd if=/dev/urandom of=/etc/pacemaker/authkey bs=4096 count=1 # scp -r /etc/pacemaker root@192.168.122.10:/etc/ ---- -Now on the +GUEST+ install pacemaker-remote package and enable the daemon to run at startup. In the commands below you will notice the 'pacemaker' and 'pacemaker_remote' packages are being installed. The 'pacemaker' package is not required. The only reason it is being installed for this tutorial is because it contains the a 'Dummy' resource agent we will be using later on to test the remote-node. +Now on the 'guest', install the pacemaker-remote package, and enable the daemon +to run at startup. In the commands below, you will notice the pacemaker +package is also installed. It is not required; the only reason it is being +installed for this tutorial is because it contains the Dummy resource agent +that we will use later for testing. -[source,C] ---- # yum install -y pacemaker pacemaker-remote resource-agents # systemctl enable pacemaker_remote.service ---- Now start pacemaker_remote on the guest and verify the start was successful. -[source,C] ---- # systemctl start pacemaker_remote.service # systemctl status pacemaker_remote pacemaker_remote.service - Pacemaker Remote Service Loaded: loaded (/usr/lib/systemd/system/pacemaker_remote.service; enabled) Active: active (running) since Thu 2013-03-14 18:24:04 EDT; 2min 8s ago Main PID: 1233 (pacemaker_remot) CGroup: name=systemd:/system/pacemaker_remote.service └─1233 /usr/sbin/pacemaker_remoted Mar 14 18:24:04 guest1 systemd[1]: Starting Pacemaker Remote Service... Mar 14 18:24:04 guest1 systemd[1]: Started Pacemaker Remote Service. Mar 14 18:24:04 guest1 pacemaker_remoted[1233]: notice: lrmd_init_remote_tls_server: Starting a tls listener on port 3121. ---- === Verify Host Connection to Guest === -Before moving forward it's worth going ahead and verifying the host can contact the guest on port 3121. Here's a trick you can use. Connect using telnet from the host. The connection will get destroyed, but how it is destroyed tells you whether it worked or not. +Before moving forward, it's worth verifying that the host can contact the guest +on port 3121. Here's a trick you can use. Connect using ssh from the host. The +connection will get destroyed, but how it is destroyed tells you whether it +worked or not. First add guest1 to the host machine's /etc/hosts file if you haven't already. This is required unless you have dns setup in a way where guest1's address can be discovered. -[source,C] ---- # cat << END >> /etc/hosts 192.168.122.10 guest1 END ---- -If running the telnet command on the host results in this output before disconnecting, the connection works. -[source,C] +If running the ssh command on one of the cluster nodes results in this +output before disconnecting, the connection works. ---- -# telnet guest1 3121 - Trying 192.168.122.10... - Connected to guest1. - Escape character is '^]'. - Connection closed by foreign host. +# ssh -p 3121 guest1 +ssh_exchange_identification: read: Connection reset by peer ---- If you see this, the connection is not working. -[source,C] ---- -# telnet guest1 3121 -Trying 192.168.122.10... -telnet: connect to address 192.168.122.10: No route to host +# ssh -p 3121 guest1 +ssh: connect to host guest1 port 3121: No route to host ---- Once you can successfully connect to the guest from the host, shutdown the guest. Pacemaker will be managing the virtual machine from this point forward. -== Step3: Integrate KVM guest into Cluster. == +== Integrate Guest into Cluster == Now the fun part, integrating the virtual machine you've just created into the cluster. It is incredibly simple. === Start the Cluster === On the host, start pacemaker. -[source,C] ---- # pcs cluster start ---- -Wait for the host to become the DC. The output of 'pcs status' should look similar to this after about a minute. +Wait for the host to become the DC. The output of `pcs status` should look +similar to this after about a minute. -[source,C] ---- Last updated: Thu Mar 14 16:41:22 2013 Last change: Thu Mar 14 16:41:08 2013 via crmd on example-host Stack: corosync Current DC: example-host (1795270848) - partition WITHOUT quorum Version: 1.1.10 1 Nodes configured, unknown expected votes 0 Resources configured. Online: [ example-host ] ---- -Now enable the cluster to work without quorum or stonith. This is required just for the sake of getting this tutorial to work with a single cluster-node. +Now enable the cluster to work without quorum or stonith. This is required +just for the sake of getting this tutorial to work with a single cluster node. -[source,C] ---- # pcs property set stonith-enabled=false # pcs property set no-quorum-policy=ignore ---- -=== Integrate KVM Guest as remote-node === +=== Integrate as Guest Node === If you didn't already do this earlier in the verify host to guest connection section, add the KVM guest's ip to the host's /etc/hosts file so we can connect by hostname. The command below will do that if you used the same ip address I used earlier. -[source,C] ---- # cat << END >> /etc/hosts 192.168.122.10 guest1 END ---- -We will use the +VirtualDomain+ resource agent for the management of the virtual machine. This agent requires the virtual machine's xml config to be dumped to a file on disk. To do this pick out the name of the virtual machine you just created from the output of this list. +We will use the *VirtualDomain* resource agent for the management of the +virtual machine. This agent requires the virtual machine's XML config to be +dumped to a file on disk. To do this, pick out the name of the virtual machine +you just created from the output of this list. -[source,C] ----- +.... # virsh list --all Id Name State -______________________________________________ +---------------------------------------------------- - guest1 shut off ----- +.... In my case I named it guest1. Dump the xml to a file somewhere on the host using the following command. -[source,C] ---- # virsh dumpxml guest1 > /root/guest1.xml ---- Now just register the resource with pacemaker and you're set! -[source,C] ---- # pcs resource create vm-guest1 VirtualDomain hypervisor="qemu:///system" config="/root/guest1.xml" meta remote-node=guest1 ---- -Once the 'vm-guest1' resource is started you will see 'guest1' appear in the 'pcs status' output as a node. The final 'pcs status' output should look something like this. +Once the *vm-guest1* resource is started you will see *guest1* appear in the +`pcs status` output as a node. The final `pcs status` output should look +something like this. -[source,C] ---- Last updated: Fri Mar 15 09:30:30 2013 Last change: Thu Mar 14 17:21:35 2013 via cibadmin on example-host Stack: corosync Current DC: example-host (1795270848) - partition WITHOUT quorum Version: 1.1.10 2 Nodes configured, unknown expected votes 2 Resources configured. Online: [ example-host guest1 ] Full list of resources: vm-guest1 (ocf::heartbeat:VirtualDomain): Started example-host ---- === Starting Resources on KVM Guest === -The commands below demonstrate how resources can be executed on both the remote-node and the cluster-node. +The commands below demonstrate how resources can be executed on both the +guest node and the cluster node. Create a few Dummy resources. Dummy resources are real resource agents used just for testing purposes. They actually execute on the host they are assigned to just like an apache server or database would, except their execution just means a file was created. When the resource is stopped, that the file it created is removed. -[source,C] ---- # pcs resource create FAKE1 ocf:pacemaker:Dummy # pcs resource create FAKE2 ocf:pacemaker:Dummy # pcs resource create FAKE3 ocf:pacemaker:Dummy # pcs resource create FAKE4 ocf:pacemaker:Dummy # pcs resource create FAKE5 ocf:pacemaker:Dummy ---- -Now check your 'pcs status' output. In the resource section you should see something like the following, where some of the resources got started on the cluster-node, and some started on the remote-node. +Now check your `pcs status` output. In the resource section, you should see +something like the following, where some of the resources started on the +cluster node, and some started on the guest node. -[source,C] ---- Full list of resources: vm-guest1 (ocf::heartbeat:VirtualDomain): Started example-host FAKE1 (ocf::pacemaker:Dummy): Started guest1 FAKE2 (ocf::pacemaker:Dummy): Started guest1 FAKE3 (ocf::pacemaker:Dummy): Started example-host FAKE4 (ocf::pacemaker:Dummy): Started guest1 FAKE5 (ocf::pacemaker:Dummy): Started example-host ---- -The remote-node, 'guest1', reacts just like any other node in the cluster. For example, pick out a resource that is running on your cluster-node. For my purposes I am picking FAKE3 from the output above. We can force FAKE3 to run on 'guest1' in the exact same way we would any other node. +The guest node, *guest1*, reacts just like any other node in the cluster. For +example, pick out a resource that is running on your cluster node. For my +purposes, I am picking FAKE3 from the output above. We can force FAKE3 to run +on *guest1* in the exact same way we would any other node. -[source,C] ---- # pcs constraint FAKE3 prefers guest1 ---- -Now looking at the bottom of the 'pcs status' output you'll see FAKE3 is on 'guest1'. +Now, looking at the bottom of the `pcs status` output you'll see FAKE3 is on +*guest1*. -[source,C] ---- Full list of resources: vm-guest1 (ocf::heartbeat:VirtualDomain): Started example-host FAKE1 (ocf::pacemaker:Dummy): Started guest1 FAKE2 (ocf::pacemaker:Dummy): Started guest1 FAKE3 (ocf::pacemaker:Dummy): Started guest1 FAKE4 (ocf::pacemaker:Dummy): Started example-host FAKE5 (ocf::pacemaker:Dummy): Started example-host ---- -=== Testing Remote-node Recovery and Fencing === +=== Testing Recovery and Fencing === -Pacemaker's policy engine is smart enough to know fencing remote-nodes associated with a virtual machine means shutting off/rebooting the virtual machine. No special configuration is necessary to make this happen. If you are interested in testing this functionality out, trying stopping the guest's pacemaker_remote daemon. This would be equivalent of abruptly terminating a cluster-node's corosync membership without properly shutting it down. +Pacemaker's policy engine is smart enough to know fencing guest nodes +associated with a virtual machine means shutting off/rebooting the virtual +machine. No special configuration is necessary to make this happen. If you +are interested in testing this functionality out, trying stopping the guest's +pacemaker_remote daemon. This would be equivalent of abruptly terminating a +cluster node's corosync membership without properly shutting it down. ssh into the guest and run this command. -[source,C] ---- # kill -9 `pidof pacemaker_remoted` ---- -After a few seconds or so you'll see this in your 'pcs status' output. The 'guest1' node will be show as offline as it is being recovered. +After a few seconds or so, you'll see this in your `pcs status` output. The +*guest1* node will be show as offline as it is being recovered. -[source,C] ---- Last updated: Fri Mar 15 11:00:31 2013 Last change: Fri Mar 15 09:54:16 2013 via cibadmin on example-host Stack: corosync Current DC: example-host (1795270848) - partition WITHOUT quorum Version: 1.1.10 2 Nodes configured, unknown expected votes 7 Resources configured. Online: [ example-host ] OFFLINE: [ guest1 ] Full list of resources: vm-guest1 (ocf::heartbeat:VirtualDomain): Started example-host FAKE1 (ocf::pacemaker:Dummy): Stopped FAKE2 (ocf::pacemaker:Dummy): Stopped FAKE3 (ocf::pacemaker:Dummy): Stopped FAKE4 (ocf::pacemaker:Dummy): Started example-host FAKE5 (ocf::pacemaker:Dummy): Started example-host Failed actions: guest1_monitor_30000 (node=example-host, call=3, rc=7, status=complete): not running ---- -Once recovery of the guest is complete, you'll see it automatically get re-integrated into the cluster. The final 'pcs status' output should look something like this. +Once recovery of the guest is complete, you'll see it automatically get +re-integrated into the cluster. The final `pcs status` output should look +something like this. -[source,C] ---- Last updated: Fri Mar 15 11:03:17 2013 Last change: Fri Mar 15 09:54:16 2013 via cibadmin on example-host Stack: corosync Current DC: example-host (1795270848) - partition WITHOUT quorum Version: 1.1.10 2 Nodes configured, unknown expected votes 7 Resources configured. Online: [ example-host guest1 ] Full list of resources: vm-guest1 (ocf::heartbeat:VirtualDomain): Started example-host FAKE1 (ocf::pacemaker:Dummy): Started guest1 FAKE2 (ocf::pacemaker:Dummy): Started guest1 FAKE3 (ocf::pacemaker:Dummy): Started guest1 FAKE4 (ocf::pacemaker:Dummy): Started example-host FAKE5 (ocf::pacemaker:Dummy): Started example-host Failed actions: guest1_monitor_30000 (node=example-host, call=3, rc=7, status=complete): not running ---- -=== Accessing Cluster Tools from Remote-node === +=== Accessing Cluster Tools from Guest Node === -Besides just allowing the cluster to manage resources on a remote-node, pacemaker_remote has one other trick. +The pacemaker_remote daemon allows nearly all the pacemaker tools (crm_resource, crm_mon, crm_attribute, crm_master) to work on remote nodes natively.+ +Besides allowing the cluster to manage resources on a guest node, +pacemaker_remote has one other trick. The pacemaker_remote daemon allows +nearly all the pacemaker tools (`crm_resource`, `crm_mon`, `crm_attribute`, +`crm_master`, etc.) to work on guest nodes natively. -Try it, run +crm_mon+ or +pcs status+ on the guest after pacemaker has integrated the remote-node into the cluster. These tools just work. These means resource agents such as master/slave resources which need access to tools like crm_master work seamlessly on the remote-nodes. +Try it: Run `crm_mon` on the guest after pacemaker has +integrated the guest node into the cluster. These tools just work. This +means resource agents such as master/slave resources which need access to tools +like `crm_master` work seamlessly on the guest nodes. +Higher-level command shells such as `pcs` may have partial support +on guest nodes, but it is recommended to run them from a cluster node. diff --git a/doc/Pacemaker_Remote/en-US/Ch-LXC-Tutorial.txt b/doc/Pacemaker_Remote/en-US/Ch-LXC-Tutorial.txt deleted file mode 100644 index 9b14effe09..0000000000 --- a/doc/Pacemaker_Remote/en-US/Ch-LXC-Tutorial.txt +++ /dev/null @@ -1,314 +0,0 @@ -= Linux Container (LXC) Walk-through = - -+Warning: Continued development in the VirtualDomain agent, libvirt, and the lxc_autogen script have rendered this tutorial (in its current form) obsolete.+ The high level approach of this tutorial remains accurate, but many of the specifics related to configuring the lxc environment have changed. This walk-through needs to be updated to reflect the current tested methodology. - -+What this tutorial is:+ This tutorial demonstrates how pacemaker_remote can be used with Linux containers (managed by libvirt-lxc) to run cluster resources in an isolated environment. - -+What this tutorial is not:+ This tutorial is not a realistic deployment scenario. The steps shown here are meant to introduce users to the concept of managing Linux container environments with Pacemaker. - -== Step 1: Setup LXC Host == - -This tutorial was tested with Fedora 18. Anything that is capable of running libvirt and pacemaker v1.1.10 or greater will do though. An installation guide for installing Fedora 18 can be found here, http://docs.fedoraproject.org/en-US/Fedora/18/html/Installation_Guide/. - -Fedora 18 (or similar distro) host preparation steps. - -=== SElinux and Firewall Rules === -In order to simply this tutorial we will disable the selinux and the firewall on the host. -WARNING: These actions pose a significant security issues to machines exposed to the outside world. Basically, just don't do this on your production system. -[source,C] ----- -# setenforce 0 -# sed -i.bak "s/SELINUX=enforcing/SELINUX=permissive/g" /etc/selinux/config -# firewall-cmd --add-port 3121/tcp --permanent - -# systemctl disable iptables.service -# systemctl disable ip6tables.service -# rm '/etc/systemd/system/basic.target.wants/iptables.service' -# rm '/etc/systemd/system/basic.target.wants/ip6tables.service' -# systemctl stop iptables.service -# systemctl stop ip6tables.service ----- - -=== Install Cluster Software on Host === - -[source,C] ----- -# yum install -y pacemaker pacemaker-remote corosync pcs resource-agents ----- - -=== Configure Corosync === - -Corosync handles pacemaker's cluster membership and messaging. The corosync config file is located in /etc/corosync/corosync.conf. That config file must be initialized with information about the cluster-nodes before pacemaker can start. - -To initialize the corosync config file, execute the following pcs command on both nodes filling in the information in <> with your nodes' information. -[source,C] ----- -# pcs cluster setup --local mycluster ----- - -A recent syntax change in pcs may cause the above command to fail. If so try this alternative. -[source,C] ----- -# pcs cluster setup --force --local --name mycluster ----- - -=== Verify Cluster === - -Start the cluster - -[source,C] ----- -# pcs cluster start ----- - -Verify corosync membership - -[source,C] ----- -# pcs status corosync - -Membership information - Nodeid Votes Name -1795270848 1 example-host (local) ----- - -Verify pacemaker status. At first the 'pcs cluster status' output will look like this. - -[source,C] ----- -# pcs status - - Last updated: Thu Mar 14 12:26:00 2013 - Last change: Thu Mar 14 12:25:55 2013 via crmd on example-host - Stack: corosync - Current DC: - Version: 1.1.10 - 1 Nodes configured, unknown expected votes - 0 Resources configured. ----- - -After about a minute you should see your host as a single node in the cluster. - -[source,C] ----- -# pcs status - - Last updated: Thu Mar 14 12:28:23 2013 - Last change: Thu Mar 14 12:25:55 2013 via crmd on example-host - Stack: corosync - Current DC: example-host (1795270848) - partition WITHOUT quorum - Version: 1.1.8-9b13ea1 - 1 Nodes configured, unknown expected votes - 0 Resources configured. - - Online: [ example-host ] ----- - -Go ahead and stop the cluster for now after verifying everything is in order. - -[source,C] ----- -# pcs cluster stop ----- - -== Step 2: Setup LXC Environment == - -=== Install Libvirt LXC software === - -[source,C] ----- -# yum install -y libvirt libvirt-daemon-lxc wget -# systemctl enable libvirtd ----- - -At this point, restart the host. - -=== Generate Libvirt LXC domains === - -I've attempted to simply this tutorial by creating a script to auto generate the libvirt-lxc xml domain definitions. - -Download the script to whatever directory you want the containers to live in. In this example I am using the /root/lxc/ directory. - -[source,C] ----- -# mkdir /root/lxc/ -# cd /root/lxc/ -# wget https://raw.github.com/davidvossel/pcmk-lxc-autogen/master/lxc-autogen -# chmod 755 lxc-autogen ----- - -Now execute the script. - -[source,C] ----- -# ./lxc-autogen ----- - -After executing the script you will see a bunch of directories and xml files are generated. Those xml files are the libvirt-lxc domain definitions, and the directories are used as some special mount points for each container. If you open up one of the xml files you'll be able to see how the cpu, memory, and filesystem resources for the container are defined. You can use the libvirt-lxc driver's documentation found here, http://libvirt.org/drvlxc.html, as a reference to help understand all the parts of the xml file. The lxc-autogen script is not complicated and is worth exploring in order to grasp how the environment is generated. - -It is worth noting that this environment is dependent on use of libvirt's default network interface. Verify the commands below look the same as your environment. The default network address 192.168.122.1 should have been generated by automatically when you installed the virtualization software. - -[source,C] ----- -# virsh net-list -Name State Autostart Persistent -________________________________________________________ -default active yes yes - -# virsh net-dumpxml default | grep -e "ip address=" - - ----- - -=== Generate the Authkey === - -Generate the authkey used to secure connections between the host and the lxc guest pacemaker_remote instances. This is sort of a funny case because the lxc guests and the host will share the same key file in the /etc/pacemaker/ directory. If in a different deployment where the lxc guests do not share the host's /etc/pacemaker directory, this key will have to be copied into each lxc guest. - -[source,C] ----- -# dd if=/dev/urandom of=/etc/pacemaker/authkey bs=4096 count=1 ----- - -== Step 3: Integrate LXC guests into Cluster. == - -=== Start Cluster === -On the host, start pacemaker. - -[source,C] ----- -# pcs cluster start ----- - -Wait for the host to become the DC. The output of 'pcs status' should look similar to this after about a minute. - -[source,C] ----- -Last updated: Thu Mar 14 16:41:22 2013 -Last change: Thu Mar 14 16:41:08 2013 via crmd on example-host -Stack: corosync -Current DC: example-host (1795270848) - partition WITHOUT quorum -Version: 1.1.10 -1 Nodes configured, unknown expected votes -0 Resources configured. - - -Online: [ example-host ] ----- - -Now enable the cluster to work without quorum or stonith. This is required just for the sake of getting this tutorial to work with a single cluster-node. - -[source,C] ----- -# pcs property set stonith-enabled=false -# pcs property set no-quorum-policy=ignore ----- - -=== Integrate LXC Guests as remote-nodes === - -If you ran the 'lxc-autogen' script with default parameters, 3 lxc domain definitions were created as .xml files. If you used the same directory I used for the lxc environment, the config files will be located in /root/lxc. Replace the 'config' parameters in the following pcs commands if yours should be different. - -The pcs commands below each configure a lxc guest as a remote-node in pacemaker. Behind the scenes each lxc guest is launching an instance of pacemaker_remote allowing pacemaker to integrate the lxc guests as remote-nodes. The meta-attribute 'remote-node=' used in each command is what tells pacemaker that the lxc guest is both a resource and a remote-node capable of running resources. In this case, the 'remote-node' attribute also indicates to pacemaker that it can contact each lxc's pacemaker_remote service by using the remote-node name as the hostname. If you look in the /etc/hosts/ file you will see entries for each lxc guest. These entries were auto-generated earlier by the 'lxc-autogen' script. - -[source,C] ----- -# pcs resource create container1 VirtualDomain force_stop="true" hypervisor="lxc:///" config="/root/lxc/lxc1.xml" meta remote-node=lxc1 -# pcs resource create container2 VirtualDomain force_stop="true" hypervisor="lxc:///" config="/root/lxc/lxc2.xml" meta remote-node=lxc2 -# pcs resource create container3 VirtualDomain force_stop="true" hypervisor="lxc:///" config="/root/lxc/lxc3.xml" meta remote-node=lxc3 ----- - - -After creating the container resources you 'pcs status' should look like this. - -[source,C] ----- -Last updated: Mon Mar 18 17:15:46 2013 -Last change: Mon Mar 18 17:15:26 2013 via cibadmin on guest1 -Stack: corosync -Current DC: example-host (175810752) - partition WITHOUT quorum -Version: 1.1.10 -4 Nodes configured, unknown expected votes -6 Resources configured. - -Online: [ example-host lxc1 lxc2 lxc3 ] - -Full list of resources: - - container3 (ocf::heartbeat:VirtualDomain): Started example-host - container1 (ocf::heartbeat:VirtualDomain): Started example-host - container2 (ocf::heartbeat:VirtualDomain): Started example-host ----- - - -=== Starting Resources on LXC Guests === - -Now that the lxc guests are integrated into the cluster, lets generate some Dummy resources to run on them. - -Dummy resources are real resource agents used just for testing purposes. They actually execute on the node they are assigned to just like an apache server or database would, except their execution just means a file was created. When the resource is stopped, that the file it created is removed. - -[source,C] ----- -# pcs resource create FAKE1 ocf:pacemaker:Dummy -# pcs resource create FAKE2 ocf:pacemaker:Dummy -# pcs resource create FAKE3 ocf:pacemaker:Dummy -# pcs resource create FAKE4 ocf:pacemaker:Dummy -# pcs resource create FAKE5 ocf:pacemaker:Dummy ----- - - -After creating the Dummy resources you will see that the resource got distributed among all the nodes. The 'pcs status' output should look similar to this. - -[source,C] ----- -Last updated: Mon Mar 18 17:31:54 2013 -Last change: Mon Mar 18 17:31:05 2013 via cibadmin on example-host -Stack: corosync -Current DC: example=host (175810752) - partition WITHOUT quorum -Version: 1.1.10 -4 Nodes configured, unknown expected votes -11 Resources configured. - - -Online: [ example-host lxc1 lxc2 lxc3 ] - -Full list of resources: - - container3 (ocf::heartbeat:VirtualDomain): Started example-host - container1 (ocf::heartbeat:VirtualDomain): Started example-host - container2 (ocf::heartbeat:VirtualDomain): Started example-host - FAKE1 (ocf::pacemaker:Dummy): Started lxc1 - FAKE2 (ocf::pacemaker:Dummy): Started lxc2 - FAKE3 (ocf::pacemaker:Dummy): Started lxc3 - FAKE4 (ocf::pacemaker:Dummy): Started lxc1 - FAKE5 (ocf::pacemaker:Dummy): Started lxc2 ----- - -To witness that Dummy agents are running within the lxc guests browse one of the lxc domain's filesystem folders. Each lxc guest has a custom mount point for the '/var/run/'directory, which is the location the Dummy resources write their state files to. - -[source,C] ----- -# ls lxc1-filesystem/var/run/ -Dummy-FAKE4.state Dummy-FAKE.state ----- - -If you are curious, take a look at lxc1.xml to see how the filesystem is mounted. - -=== Testing LXC Guest Failure === - -You will be able to see each pacemaker_remoted process running in each lxc guest from the host machine. - -[source,C] ----- -# ps -A | grep -e pacemaker_remote* - 9142 pts/2 00:00:00 pacemaker_remot -10148 pts/4 00:00:00 pacemaker_remot -10942 pts/6 00:00:00 pacemaker_remot ----- - -In order to see how the cluster reacts to a failed lxc guest. Try killing one of the pacemaker_remote instances. - -[source,C] ----- -# kill -9 9142 ----- - -After a few moments the lxc guest that was running that instance of pacemaker_remote will be recovered along with all the resources running within that container. diff --git a/doc/Pacemaker_Remote/en-US/Ch-Options.txt b/doc/Pacemaker_Remote/en-US/Ch-Options.txt index 5d68b4f9d0..abe511fd35 100644 --- a/doc/Pacemaker_Remote/en-US/Ch-Options.txt +++ b/doc/Pacemaker_Remote/en-US/Ch-Options.txt @@ -1,77 +1,115 @@ = Configuration Explained = -The walk-through examples use some of these options, but don't explain exactly what they mean or do. This section is meant to be the go-to resource for all the options available for configuring remote-nodes. +The walk-through examples use some of these options, but don't explain exactly +what they mean or do. This section is meant to be the go-to resource for all +the options available for configuring pacemaker_remote-based nodes. +(((configuration))) -== Container remote-node Resource Options == +== Resource Meta-Attributes for Guest Nodes == -When configuring a virtual machine or lxc resource to act as a remote-node, these are the metadata options available to both enable the resource as a remote-node and define the connection parameters. +When configuring a virtual machine to use as a guest node, these are the +metadata options available to enable the resource as a guest node and +define its connection parameters. -.Metadata Options for configuring KVM/LXC resources as remote-nodes -[width="95%",cols="1m,1,4<",options="header",align="center"] +.Meta-attributes for configuring VM resources as guest nodes +[width="95%",cols="2m,1,4<",options="header",align="center"] |========================================================= |Option |Default |Description -|+remote-node+ -| -|The name of the remote-node this resource defines. This both enables the resource as a remote-node and defines the unique name used to identify the remote-node. If no other parameters are set, this value will also be assumed as the hostname to connect to at port 3121. +WARNING+ This value cannot overlap with any resource or node IDs. +|remote-node +|'none' +|The node name of the guest node this resource defines. This both enables the +resource as a guest node and defines the unique name used to identify the +guest node. If no other parameters are set, this value will also be assumed as +the hostname to use when connecting to pacemaker_remote on the VM. This value +*must not* overlap with any resource or node IDs. -|+remote-port+ +|remote-port |3121 -|Configure a custom port to use for the guest connection to pacemaker_remote. +|The port on the virtual machine that the cluster will use to connect to +pacemaker_remote. -|+remote-addr+ -|+remote-node+ value used as hostname -|The ip address or hostname to connect to if remote-node's name is not the hostname of the guest. +|remote-addr +|'value of' +remote-node+ +|The IP address or hostname to use when connecting to pacemaker_remote on the VM. -|+remote-connect-timeout+ +|remote-connect-timeout |60s |How long before a pending guest connection will time out. |========================================================= -== Baremetal remote-node Options == +== Connection Resources for Remote Nodes == -Baremetal remote-nodes are defined by a connection resource. That connection resource has the following instance attributes that define where the baremetal remote-node is located on the network and how to communicate with that remote-node. Descriptions of these options can be retrieved using the following pcs command. +A remote node is defined by a connection resource. That connection resource +has instance attributes that define where the remote node is located on the +network and how to communicate with it. -[source,C] +Descriptions of these instance attributes can be retrieved using the following +`pcs` command: ---- # pcs resource describe remote - Resource options for: ocf:pacemaker:remote - server: Server location to connect to. This can be an ip address or hostname. - port: tcp port to connect to. +ocf:pacemaker:remote - + + + +Resource options: + server: Server location to connect to. This can be an ip address or hostname. + port: tcp port to connect to. ---- -When defining a baremetal remote-node's connection resource, it is common and recommended to name the connection resource the same name as the baremeatal remote-node's hostname. By default, if no "server" option is provided, the cluster will attempt to contact the remote-node using the resource name as the hostname. +When defining a remote node's connection resource, it is common and recommended +to name the connection resource the same as the remote node's hostname. By +default, if no *server* option is provided, the cluster will attempt to contact +the remote node using the resource name as the hostname. -Example, defining a baremetal remote-node with the hostname "remote1" -[source,C] +Example defining a remote node with the hostname *remote1*: ---- # pcs resource create remote1 remote ---- -Example, defining a baremetal remote-node to connect to a specific ip and port. -[source,C] +Example defining a remote node to connect to a specific IP address and port: ---- # pcs resource create remote1 remote server=192.168.122.200 port=8938 ---- -== Host and Guest Authentication == +== Environment Variables for Daemon Start-up == -Authentication and encryption of the connection between cluster-nodes (pacemaker) to remote-nodes (pacemaker_remote) is achieved using TLS with PSK encryption/authentication on +tcp port 3121+. This means both the cluster-node and remote-node must share the same private key. By default this +key must be placed at "/etc/pacemaker/authkey" on both cluster-nodes and remote-nodes+. +Authentication and encryption of the connection between cluster nodes +and nodes running pacemaker_remote is achieved using +with https://en.wikipedia.org/wiki/TLS-PSK[TLS-PSK] encryption/authentication +over TCP (port 3121 by default). This means that both the cluster node and +remote node must share the same private key. By default, this +key is placed at +/etc/pacemaker/authkey+ on each node. -== Pacemaker and pacemaker_remote Options == - -If you need to change the default port or authkey location for either pacemaker or pacemaker_remote, there are environment variables you can set that affect both of those daemons. These environment variables can be enabled by placing them in the /etc/sysconfig/pacemaker file. -[source,C] +You can change the default port and/or key location for Pacemaker and +pacemaker_remote via environment variables. These environment variables can be +enabled by placing them in the +/etc/sysconfig/pacemaker+ file. ---- #==#==# Pacemaker Remote # Use a custom directory for finding the authkey. PCMK_authkey_location=/etc/pacemaker/authkey # # Specify a custom port for Pacemaker Remote connections PCMK_remote_port=3121 ---- +== Removing Remote Nodes and Guest Nodes == + +If the resource creating a guest node, or the *ocf:pacemaker:remote* resource +creating a connection to a remote node, is removed from the configuration, the +affected node will continue to show up in output as an offline node. + +If you want to get rid of that output, run (replacing $NODE_NAME appropriately): +---- +# crm_node --force --remove $NODE_NAME +---- + +[WARNING] +========= +Be absolutely sure that the node's resource has been deleted from the +configuration first. +========= diff --git a/doc/Pacemaker_Remote/en-US/Pacemaker_Remote.ent b/doc/Pacemaker_Remote/en-US/Pacemaker_Remote.ent index be6171c50d..8a9d4f932b 100644 --- a/doc/Pacemaker_Remote/en-US/Pacemaker_Remote.ent +++ b/doc/Pacemaker_Remote/en-US/Pacemaker_Remote.ent @@ -1,6 +1,6 @@ - + - - + + diff --git a/doc/Pacemaker_Remote/en-US/Pacemaker_Remote.xml b/doc/Pacemaker_Remote/en-US/Pacemaker_Remote.xml index 9a5e119481..3867314a33 100644 --- a/doc/Pacemaker_Remote/en-US/Pacemaker_Remote.xml +++ b/doc/Pacemaker_Remote/en-US/Pacemaker_Remote.xml @@ -1,18 +1,17 @@ %BOOK_ENTITIES; ]> - - + diff --git a/doc/Pacemaker_Remote/en-US/Revision_History.xml b/doc/Pacemaker_Remote/en-US/Revision_History.xml index af25ebe72a..269b549a11 100644 --- a/doc/Pacemaker_Remote/en-US/Revision_History.xml +++ b/doc/Pacemaker_Remote/en-US/Revision_History.xml @@ -1,31 +1,37 @@ %BOOK_ENTITIES; ]> Revision History 1-0 Tue Mar 19 2013 DavidVosseldavidvossel@gmail.com Import from Pages.app 2-0 Tue May 13 2013 DavidVosseldavidvossel@gmail.com Added Future Features Section 3-0 Fri Oct 18 2013 DavidVosseldavidvossel@gmail.com Added Baremetal remote-node feature documentation + + 4-0 + Tue Aug 25 2015 + KenGaillotkgaillot@redhat.com + Targeted CentOS 7.1 and Pacemaker 1.1.12+, updated for current terminology and practice +