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diff --git a/doc/Pacemaker_Explained/en-US/Ch-Resources.txt b/doc/Pacemaker_Explained/en-US/Ch-Resources.txt
index 2d988f09bf..e0d906b04e 100644
--- a/doc/Pacemaker_Explained/en-US/Ch-Resources.txt
+++ b/doc/Pacemaker_Explained/en-US/Ch-Resources.txt
@@ -1,846 +1,846 @@
= Cluster Resources =
== What is a Cluster Resource? ==
indexterm:[Resource]
A resource is a service made highly available by a cluster.
The simplest type of resource, a 'primitive' resource, is described
in this chapter. More complex forms, such as groups and clones,
are described in later chapters.
Every primitive resource has a 'resource agent'. A resource agent is an
external program that abstracts the service it provides and present a
consistent view to the cluster.
This allows the cluster to be agnostic about the resources it manages.
The cluster doesn't need to understand how the resource works because
it relies on the resource agent to do the right thing when given a
`start`, `stop` or `monitor` command. For this reason, it is crucial that
resource agents are well-tested.
Typically, resource agents come in the form of shell scripts. However,
they can be written using any technology (such as C, Python or Perl)
that the author is comfortable with.
[[s-resource-supported]]
== Resource Classes ==
indexterm:[Resource,class]
Pacemaker supports several classes of agents:
* OCF
* LSB
* Upstart
* Systemd
* Service
* Fencing
* Nagios Plugins
=== Open Cluster Framework ===
indexterm:[Resource,OCF]
indexterm:[OCF,Resources]
indexterm:[Open Cluster Framework,Resources]
The OCF standard
footnote:[See
http://www.opencf.org/cgi-bin/viewcvs.cgi/specs/ra/resource-agent-api.txt?rev=HEAD
-- at least as it relates to resource agents. The Pacemaker implementation has
been somewhat extended from the OCF specs, but none of those changes are
incompatible with the original OCF specification.]
is basically an extension of the Linux Standard Base conventions for
init scripts to:
* support parameters,
* make them self-describing, and
* make them extensible
OCF specs have strict definitions of the exit codes that actions must return.
footnote:[
The resource-agents source code includes the `ocf-tester` script, which
can be useful in this regard.
]
The cluster follows these specifications exactly, and giving the wrong
exit code will cause the cluster to behave in ways you will likely
find puzzling and annoying. In particular, the cluster needs to
distinguish a completely stopped resource from one which is in some
erroneous and indeterminate state.
Parameters are passed to the resource agent as environment variables, with the
special prefix +OCF_RESKEY_+. So, a parameter which the user thinks
of as +ip+ will be passed to the resource agent as +OCF_RESKEY_ip+. The
number and purpose of the parameters is left to the resource agent; however,
the resource agent should use the `meta-data` command to advertise any that it
supports.
The OCF class is the most preferred as it is an industry standard,
highly flexible (allowing parameters to be passed to agents in a
non-positional manner) and self-describing.
For more information, see the
http://www.linux-ha.org/wiki/OCF_Resource_Agents[reference] and
<<ap-ocf>>.
=== Linux Standard Base ===
indexterm:[Resource,LSB]
indexterm:[LSB,Resources]
indexterm:[Linux Standard Base,Resources]
LSB resource agents are those found in +/etc/init.d+.
Generally, they are provided by the OS distribution and, in order to be used
with the cluster, they must conform to the LSB Spec.
footnote:[
See
http://refspecs.linux-foundation.org/LSB_3.0.0/LSB-Core-generic/LSB-Core-generic/iniscrptact.html
for the LSB Spec as it relates to init scripts.
]
[WARNING]
====
Many distributions claim LSB compliance but ship with broken init
scripts. For details on how to check whether your init script is
LSB-compatible, see <<ap-lsb>>. Common problematic violations of
the LSB standard include:
* Not implementing the status operation at all
* Not observing the correct exit status codes for `start/stop/status` actions
* Starting a started resource returns an error
* Stopping a stopped resource returns an error
====
[IMPORTANT]
====
Remember to make sure the computer is _not_ configured to start any
services at boot time -- that should be controlled by the cluster.
====
=== Systemd ===
indexterm:[Resource,Systemd]
indexterm:[Systemd,Resources]
Some newer distributions have replaced the old
http://en.wikipedia.org/wiki/Init#SysV-style["SysV"] style of
initialization daemons and scripts with an alternative called
http://www.freedesktop.org/wiki/Software/systemd[Systemd].
Pacemaker is able to manage these services _if they are present_.
Instead of init scripts, systemd has 'unit files'. Generally, the
services (unit files) are provided by the OS distribution, but there
are online guides for converting from init scripts.
footnote:[For example,
http://0pointer.de/blog/projects/systemd-for-admins-3.html]
[IMPORTANT]
====
Remember to make sure the computer is _not_ configured to start any
services at boot time -- that should be controlled by the cluster.
====
=== Upstart ===
indexterm:[Resource,Upstart]
indexterm:[Upstart,Resources]
Some newer distributions have replaced the old
http://en.wikipedia.org/wiki/Init#SysV-style["SysV"] style of
initialization daemons (and scripts) with an alternative called
http://upstart.ubuntu.com/[Upstart].
Pacemaker is able to manage these services _if they are present_.
Instead of init scripts, upstart has 'jobs'. Generally, the
services (jobs) are provided by the OS distribution.
[IMPORTANT]
====
Remember to make sure the computer is _not_ configured to start any
services at boot time -- that should be controlled by the cluster.
====
=== System Services ===
indexterm:[Resource,System Services]
indexterm:[System Service,Resources]
Since there are various types of system services (+systemd+,
+upstart+, and +lsb+), Pacemaker supports a special +service+ alias which
intelligently figures out which one applies to a given cluster node.
This is particularly useful when the cluster contains a mix of
+systemd+, +upstart+, and +lsb+.
In order, Pacemaker will try to find the named service as:
. an LSB init script
. a Systemd unit file
. an Upstart job
=== STONITH ===
indexterm:[Resource,STONITH]
indexterm:[STONITH,Resources]
The STONITH class is used exclusively for fencing-related resources. This is
discussed later in <<ch-stonith>>.
=== Nagios Plugins ===
indexterm:[Resource,Nagios Plugins]
indexterm:[Nagios Plugins,Resources]
Nagios Plugins
footnote:[The project has two independent forks, hosted at
https://www.nagios-plugins.org/ and https://www.monitoring-plugins.org/. Output
from both projects' plugins is similar, so plugins from either project can be
used with pacemaker.]
allow us to monitor services on remote hosts.
Pacemaker is able to do remote monitoring with the plugins _if they are
present_.
A common use case is to configure them as resources belonging to a resource
container (usually a virtual machine), and the container will be restarted
if any of them has failed. Another use is to configure them as ordinary
resources to be used for monitoring hosts or services via the network.
The supported parameters are same as the long options of the plugin.
[[primitive-resource]]
== Resource Properties ==
These values tell the cluster which resource agent to use for the resource,
where to find that resource agent and what standards it conforms to.
.Properties of a Primitive Resource
[width="95%",cols="1m,6<",options="header",align="center"]
|=========================================================
|Field
|Description
|id
|Your name for the resource
indexterm:[id,Resource]
indexterm:[Resource,Property,id]
|class
|The standard the resource agent conforms to. Allowed values:
+lsb+, +nagios+, +ocf+, +service+, +stonith+, +systemd+, +upstart+
indexterm:[class,Resource]
indexterm:[Resource,Property,class]
|type
|The name of the Resource Agent you wish to use. E.g. +IPaddr+ or +Filesystem+
indexterm:[type,Resource]
indexterm:[Resource,Property,type]
|provider
|The OCF spec allows multiple vendors to supply the same
resource agent. To use the OCF resource agents supplied by
the Heartbeat project, you would specify +heartbeat+ here.
indexterm:[provider,Resource]
indexterm:[Resource,Property,provider]
|=========================================================
The XML definition of a resource can be queried with the `crm_resource` tool.
For example:
----
# crm_resource --resource Email --query-xml
----
might produce:
.A system resource definition
=====
[source,XML]
<primitive id="Email" class="service" type="exim"/>
=====
[NOTE]
=====
One of the main drawbacks to system services (LSB, systemd or
Upstart) resources is that they do not allow any parameters!
=====
////
See https://tools.ietf.org/html/rfc5737 for choice of example IP address
////
.An OCF resource definition
=====
[source,XML]
-------
<primitive id="Public-IP" class="ocf" type="IPaddr" provider="heartbeat">
<instance_attributes id="Public-IP-params">
<nvpair id="Public-IP-ip" name="ip" value="192.0.2.2"/>
</instance_attributes>
</primitive>
-------
=====
[[s-resource-options]]
== Resource Options ==
Resources have two types of options: 'meta-attributes' and 'instance attributes'.
Meta-attributes apply to any type of resource, while instance attributes
are specific to each resource agent.
=== Resource Meta-Attributes ===
Meta-attributes are used by the cluster to decide how a resource should
behave and can be easily set using the `--meta` option of the
`crm_resource` command.
.Meta-attributes of a Primitive Resource
[width="95%",cols="2m,2,5<a",options="header",align="center"]
|=========================================================
|Field
|Default
|Description
|priority
|0
|If not all resources can be active, the cluster will stop lower
priority resources in order to keep higher priority ones active.
indexterm:[priority,Resource Option]
indexterm:[Resource,Option,priority]
|target-role
|Started
|What state should the cluster attempt to keep this resource in? Allowed values:
* +Stopped:+ Force the resource to be stopped
* +Started:+ Allow the resource to be started (and in the case of
<<s-resource-multistate,multi-state>> resources, promoted to master if
appropriate)
* +Slave:+ Allow the resource to be started, but only in Slave mode if
the resource is <<s-resource-multistate,multi-state>>
* +Master:+ Equivalent to +Started+
indexterm:[target-role,Resource Option]
indexterm:[Resource,Option,target-role]
|is-managed
|TRUE
|Is the cluster allowed to start and stop the resource? Allowed
values: +true+, +false+
indexterm:[is-managed,Resource Option]
indexterm:[Resource,Option,is-managed]
|resource-stickiness
|value of +resource-stickiness+ in the +rsc_defaults+ section
|How much does the resource prefer to stay where it is?
indexterm:[resource-stickiness,Resource Option]
indexterm:[Resource,Option,resource-stickiness]
|requires
|fencing (unless +stonith-enabled+ is +false+ or +class+ is
+stonith+, in which case it defaults to quorum)
|Conditions under which the resource can be started '(since 1.1.8)'
Allowed values:
* +nothing:+ can always be started
* +quorum:+ The cluster can only start this resource if a majority of
the configured nodes are active
* +fencing:+ The cluster can only start this resource if a majority
of the configured nodes are active _and_ any failed or unknown nodes
have been powered off
* +unfencing:+
The cluster can only start this resource if a majority
of the configured nodes are active _and_ any failed or unknown nodes
have been powered off _and_ only on nodes that have been 'unfenced'
'(since 1.1.9)'
indexterm:[requires,Resource Option]
indexterm:[Resource,Option,requires]
|migration-threshold
|INFINITY
|How many failures may occur for this resource on a node, before this
node is marked ineligible to host this resource. A value of 0 indicates that
this feature is disabled (the node will never be marked ineligible); by
constrast, the cluster treats INFINITY (the default) as a very large but
finite number. This option has an effect only if the failed operation has
on-fail=restart (the default), and additionally for failed start operations,
if the cluster property start-failure-is-fatal is false.
indexterm:[migration-threshold,Resource Option]
indexterm:[Resource,Option,migration-threshold]
|failure-timeout
|0
|How many seconds to wait before acting as if the failure had not
occurred, and potentially allowing the resource back to the node on
which it failed. A value of 0 indicates that this feature is disabled.
As with any time-based actions, this is not guaranteed to be checked more
frequently than the value of +cluster-recheck-interval+ (see
<<s-cluster-options>>).
indexterm:[failure-timeout,Resource Option]
indexterm:[Resource,Option,failure-timeout]
|multiple-active
|stop_start
|What should the cluster do if it ever finds the resource active on
more than one node? Allowed values:
* +block:+ mark the resource as unmanaged
* +stop_only:+ stop all active instances and leave them that way
* +stop_start:+ stop all active instances and start the resource in
one location only
indexterm:[multiple-active,Resource Option]
indexterm:[Resource,Option,multiple-active]
|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 the port specified by +remote-port+. +WARNING:+
This value cannot overlap with any resource or node IDs. If not specified,
this feature is disabled.
|remote-port
|3121
|Port to use for the guest connection to pacemaker_remote
|remote-addr
|value of +remote-node+
|The IP address or hostname to connect to if remote-node's name is not the
hostname of the guest.
|+remote-connect-timeout+
|60s
|How long before a pending guest connection will time out.
|=========================================================
[NOTE]
====
Support for remote nodes was added in pacemaker 1.1.10. If you are using an
earlier version, options related to remote nodes will not be available.
====
As an example of setting resource options, if you performed the following
commands on an LSB Email resource:
-------
# crm_resource --meta --resource Email --set-parameter priority --parameter-value 100
# crm_resource -m -r Email -p multiple-active -v block
-------
the resulting resource definition might be:
.An LSB resource with cluster options
=====
[source,XML]
-------
<primitive id="Email" class="lsb" type="exim">
<meta_attributes id="Email-meta_attributes">
<nvpair id="Email-meta_attributes-priority" name="priority" value="100"/>
<nvpair id="Email-meta_attributes-multiple-active" name="multiple-active" value="block"/>
</meta_attributes>
</primitive>
-------
=====
[[s-resource-defaults]]
=== Setting Global Defaults for Resource Meta-Attributes ===
To set a default value for a resource option, add it to the
+rsc_defaults+ section with `crm_attribute`. For example,
----
# crm_attribute --type rsc_defaults --name is-managed --update false
----
would prevent the cluster from starting or stopping any of the
resources in the configuration (unless of course the individual
resources were specifically enabled by having their +is-managed+ set to
+true+).
=== Resource Instance Attributes ===
The resource agents of some resource classes (lsb, systemd and upstart 'not' among them)
can be given parameters which determine how they behave and which instance
of a service they control.
If your resource agent supports parameters, you can add them with the
`crm_resource` command. For example,
----
# crm_resource --resource Public-IP --set-parameter ip --parameter-value 192.0.2.2
----
would create an entry in the resource like this:
.An example OCF resource with instance attributes
=====
[source,XML]
-------
<primitive id="Public-IP" class="ocf" type="IPaddr" provider="heartbeat">
<instance_attributes id="params-public-ip">
<nvpair id="public-ip-addr" name="ip" value="192.0.2.2"/>
</instance_attributes>
</primitive>
-------
=====
For an OCF resource, the result would be an environment variable
called +OCF_RESKEY_ip+ with a value of +192.0.2.2+.
The list of instance attributes supported by an OCF resource agent can be
found by calling the resource agent with the `meta-data` command.
The output contains an XML description of all the supported
attributes, their purpose and default values.
.Displaying the metadata for the Dummy resource agent template
=====
----
# export OCF_ROOT=/usr/lib/ocf
# $OCF_ROOT/resource.d/pacemaker/Dummy meta-data
----
[source,XML]
-------
<?xml version="1.0"?>
<!DOCTYPE resource-agent SYSTEM "ra-api-1.dtd">
<resource-agent name="Dummy" version="1.0">
<version>1.0</version>
<longdesc lang="en">
This is a Dummy Resource Agent. It does absolutely nothing except
keep track of whether its running or not.
Its purpose in life is for testing and to serve as a template for RA writers.
NB: Please pay attention to the timeouts specified in the actions
section below. They should be meaningful for the kind of resource
the agent manages. They should be the minimum advised timeouts,
but they shouldn't/cannot cover _all_ possible resource
instances. So, try to be neither overly generous nor too stingy,
but moderate. The minimum timeouts should never be below 10 seconds.
</longdesc>
<shortdesc lang="en">Example stateless resource agent</shortdesc>
<parameters>
<parameter name="state" unique="1">
<longdesc lang="en">
Location to store the resource state in.
</longdesc>
<shortdesc lang="en">State file</shortdesc>
<content type="string" default="/var/run/Dummy-default.state" />
</parameter>
<parameter name="fake" unique="0">
<longdesc lang="en">
Fake attribute that can be changed to cause a reload
</longdesc>
<shortdesc lang="en">Fake attribute that can be changed to cause a reload</shortdesc>
<content type="string" default="dummy" />
</parameter>
<parameter name="op_sleep" unique="1">
<longdesc lang="en">
Number of seconds to sleep during operations. This can be used to test how
the cluster reacts to operation timeouts.
</longdesc>
<shortdesc lang="en">Operation sleep duration in seconds.</shortdesc>
<content type="string" default="0" />
</parameter>
</parameters>
<actions>
<action name="start" timeout="20" />
<action name="stop" timeout="20" />
<action name="monitor" timeout="20" interval="10" depth="0"/>
<action name="reload" timeout="20" />
<action name="migrate_to" timeout="20" />
<action name="migrate_from" timeout="20" />
<action name="validate-all" timeout="20" />
<action name="meta-data" timeout="5" />
</actions>
</resource-agent>
-------
=====
== Resource Operations ==
indexterm:[Resource,Action]
'Operations' are actions the cluster can perform on a resource by calling the
resource agent. Resource agents must support certain common operations such as
start, stop and monitor, and may implement any others.
Some operations are generated by the cluster itself, for example, stopping and
starting resources as needed.
You can configure operations in the cluster configuration. As an example, by
default the cluster will 'not' ensure your resources stay healthy once they are
started. footnote:[Currently, anyway. Automatic monitoring operations may be
added in a future version of Pacemaker.] To instruct the cluster to do this,
you need to add a +monitor+ operation to the resource's definition.
.An OCF resource with a recurring health check
=====
[source,XML]
-------
<primitive id="Public-IP" class="ocf" type="IPaddr" provider="heartbeat">
<operations>
<op id="public-ip-check" name="monitor" interval="60s"/>
</operations>
<instance_attributes id="params-public-ip">
<nvpair id="public-ip-addr" name="ip" value="192.0.2.2"/>
</instance_attributes>
</primitive>
-------
=====
.Properties of an Operation
[width="95%",cols="2m,3,6<a",options="header",align="center"]
|=========================================================
|Field
|Default
|Description
|id
|
|A unique name for the operation.
indexterm:[id,Action Property]
indexterm:[Action,Property,id]
|name
|
|The action to perform. This can be any action supported by the agent; common
values include +monitor+, +start+, and +stop+.
indexterm:[name,Action Property]
indexterm:[Action,Property,name]
|interval
|0
|How frequently (in seconds) to perform the operation. A value of 0 means never.
A positive value defines a 'recurring action', which is typically used with
<<s-resource-monitoring,monitor>>.
indexterm:[interval,Action Property]
indexterm:[Action,Property,interval]
|timeout
|
|How long to wait before declaring the action has failed
indexterm:[timeout,Action Property]
indexterm:[Action,Property,timeout]
|on-fail
|restart '(except for stop operations, which default to' fence 'when
STONITH is enabled and' block 'otherwise)'
|The action to take if this action ever fails. Allowed values:
* +ignore:+ Pretend the resource did not fail.
* +block:+ Don't perform any further operations on the resource.
* +stop:+ Stop the resource and do not start it elsewhere.
* +restart:+ Stop the resource and start it again (possibly on a different node).
* +fence:+ STONITH the node on which the resource failed.
* +standby:+ Move _all_ resources away from the node on which the resource failed.
indexterm:[on-fail,Action Property]
indexterm:[Action,Property,on-fail]
|enabled
|TRUE
|If +false+, ignore this operation definition. This is typically used to pause
a particular recurring monitor operation; for instance, it can complement
the respective resource being unmanaged (+is-managed=false+), as this alone
will <<s-monitoring-unmanaged,not block any configured monitoring>>.
Disabling the operation does not suppress all actions of the given type.
Allowed values: +true+, +false+.
indexterm:[enabled,Action Property]
indexterm:[Action,Property,enabled]
|record-pending
|
|If +true+, the intention to perform the operation is recorded so that
GUIs and CLI tools can indicate that an operation is in progress.
This is best set as an 'operation default' (see next section).
Allowed values: +true+, +false+.
indexterm:[enabled,Action Property]
indexterm:[Action,Property,enabled]
|role
|
|Run the operation only on node(s) that the cluster thinks should be in
the specified role. This only makes sense for recurring monitor operations.
Allowed (case-sensitive) values: +Stopped+, +Started+, and in the
case of <<s-resource-multistate,multi-state>> resources, +Slave+ and +Master+.
indexterm:[role,Action Property]
indexterm:[Action,Property,role]
|=========================================================
[[s-resource-monitoring]]
=== Monitoring Resources for Failure ===
When Pacemaker first starts a resource, it runs one-time monitor operations
(referred to as 'probes') to ensure the resource is running where it's
supposed to be, and not running where it's not supposed to be. (This behavior
can be affected by the +resource-discovery+ location constraint property.)
Other than those initial probes, Pacemaker will not (by default) check that
the resource continues to stay healthy. As in the example above, you must
configure monitor operations explicitly to perform these checks.
By default, a monitor operation will ensure that the resource is running
where it is supposed to. The +target-role+ property can be used for further
checking.
For example, if a resource has one monitor operation with
+interval=10 role=Started+ and a second monitor operation with
+interval=11 role=Stopped+, the cluster will run the first monitor on any nodes
it thinks 'should' be running the resource, and the second monitor on any nodes
that it thinks 'should not' be running the resource (for the truly paranoid,
who want to know when an administrator manually starts a service by mistake).
[[s-monitoring-unmanaged]]
=== Monitoring Resources When Administration is Disabled ===
Recurring monitor operations behave differently under various administrative
settings:
* When a resource is unmanaged (by setting +is-managed=false+): No monitors
will be stopped.
+
If the unmanaged resource is stopped on a node where the cluster thinks it
should be running, the cluster will detect and report that it is not, but it
will not consider the monitor failed, and will not try to start the resource
until it is managed again.
+
Starting the unmanaged resource on a different node is strongly discouraged
and will at least cause the cluster to consider the resource failed, and
may require the resource's +target-role+ to be set to +Stopped+ then +Started+
to be recovered.
* When a node is put into standby: All resources will be moved away from the
node, and all monitor operations will be stopped on the node, except those
with +role=Stopped+. Monitor operations with +role=Stopped+ will be started
on the node if appropriate.
* When the cluster is put into maintenance mode: All resources will be marked
as unmanaged. All monitor operations will be stopped, except those with
+role=Stopped+. As with single unmanaged resources, starting a resource
on a node other than where the cluster expects it to be will cause problems.
[[s-operation-defaults]]
=== Setting Global Defaults for Operations ===
You can change the global default values for operation properties
in a given cluster. These are defined in an +op_defaults+ section
of the CIB's +configuration+ section, and can be set with `crm_attribute`.
For example,
----
# crm_attribute --type op_defaults --name timeout --update 20s
----
would default each operation's +timeout+ to 20 seconds. If an
operation's definition also includes a value for +timeout+, then that
value would be used for that operation instead.
=== When Implicit Operations Take a Long Time ===
The cluster will always perform a number of implicit operations: +start+,
+stop+ and a non-recurring +monitor+ operation used at startup to check
whether the resource is already active. If one of these is taking too long,
then you can create an entry for them and specify a longer timeout.
.An OCF resource with custom timeouts for its implicit actions
=====
[source,XML]
-------
<primitive id="Public-IP" class="ocf" type="IPaddr" provider="heartbeat">
<operations>
<op id="public-ip-startup" name="monitor" interval="0" timeout="90s"/>
<op id="public-ip-start" name="start" interval="0" timeout="180s"/>
<op id="public-ip-stop" name="stop" interval="0" timeout="15min"/>
</operations>
<instance_attributes id="params-public-ip">
<nvpair id="public-ip-addr" name="ip" value="192.0.2.2"/>
</instance_attributes>
</primitive>
-------
=====
=== Multiple Monitor Operations ===
Provided no two operations (for a single resource) have the same name
and interval, you can have as many monitor operations as you like. In
this way, you can do a superficial health check every minute and
progressively more intense ones at higher intervals.
To tell the resource agent what kind of check to perform, you need to
provide each monitor with a different value for a common parameter.
The OCF standard creates a special parameter called +OCF_CHECK_LEVEL+
for this purpose and dictates that it is "made available to the
resource agent without the normal +OCF_RESKEY+ prefix".
Whatever name you choose, you can specify it by adding an
+instance_attributes+ block to the +op+ tag. It is up to each
resource agent to look for the parameter and decide how to use it.
.An OCF resource with two recurring health checks, performing different levels of checks specified via +OCF_CHECK_LEVEL+.
=====
[source,XML]
-------
<primitive id="Public-IP" class="ocf" type="IPaddr" provider="heartbeat">
<operations>
<op id="public-ip-health-60" name="monitor" interval="60">
<instance_attributes id="params-public-ip-depth-60">
<nvpair id="public-ip-depth-60" name="OCF_CHECK_LEVEL" value="10"/>
</instance_attributes>
</op>
<op id="public-ip-health-300" name="monitor" interval="300">
<instance_attributes id="params-public-ip-depth-300">
<nvpair id="public-ip-depth-300" name="OCF_CHECK_LEVEL" value="20"/>
- </instance_attributes>
+ </instance_attributes>
</op>
</operations>
<instance_attributes id="params-public-ip">
<nvpair id="public-ip-level" name="ip" value="192.0.2.2"/>
</instance_attributes>
</primitive>
-------
=====
=== Disabling a Monitor Operation ===
The easiest way to stop a recurring monitor is to just delete it.
However, there can be times when you only want to disable it
temporarily. In such cases, simply add +enabled="false"+ to the
operation's definition.
.Example of an OCF resource with a disabled health check
=====
[source,XML]
-------
<primitive id="Public-IP" class="ocf" type="IPaddr" provider="heartbeat">
<operations>
<op id="public-ip-check" name="monitor" interval="60s" enabled="false"/>
</operations>
<instance_attributes id="params-public-ip">
<nvpair id="public-ip-addr" name="ip" value="192.0.2.2"/>
</instance_attributes>
</primitive>
-------
=====
This can be achieved from the command line by executing:
----
# cibadmin --modify --xml-text '<op id="public-ip-check" enabled="false"/>'
----
Once you've done whatever you needed to do, you can then re-enable it with
----
# cibadmin --modify --xml-text '<op id="public-ip-check" enabled="true"/>'
----
diff --git a/doc/Pacemaker_Explained/en-US/Ch-Rules.txt b/doc/Pacemaker_Explained/en-US/Ch-Rules.txt
index 986a6aac8b..77c98885a2 100644
--- a/doc/Pacemaker_Explained/en-US/Ch-Rules.txt
+++ b/doc/Pacemaker_Explained/en-US/Ch-Rules.txt
@@ -1,600 +1,600 @@
= Rules =
////
We prefer [[ch-rules]], but older versions of asciidoc don't deal well
with that construct for chapter headings
////
anchor:ch-rules[Chapter 8, Rules]
indexterm:[Resource,Constraint,Rule]
Rules can be used to make your configuration more dynamic. One common
example is to set one value for +resource-stickiness+ during working
hours, to prevent resources from being moved back to their most
preferred location, and another on weekends when no-one is around to
notice an outage.
Another use of rules might be to assign machines to different
processing groups (using a node attribute) based on time and to then
use that attribute when creating location constraints.
Each rule can contain a number of expressions, date-expressions and
even other rules. The results of the expressions are combined based
on the rule's +boolean-op+ field to determine if the rule ultimately
evaluates to +true+ or +false+. What happens next depends on the
context in which the rule is being used.
== Rule Properties ==
.Properties of a Rule
[width="95%",cols="2m,1,5<",options="header",align="center"]
|=========================================================
|Field
|Default
|Description
|role
|+Started+
|Limits the rule to apply only when the resource is in the specified
role. Allowed values are +Started+, +Slave+, and +Master+. A rule
with +role="Master"+ cannot determine the initial location of a
clone instance and will only affect which of the active instances
will be promoted.
indexterm:[role,Constraint Rule]
indexterm:[Constraint,Rule,role]
|score
|
|The score to apply if the rule evaluates to +true+. Limited to use in
rules that are part of location constraints.
indexterm:[score,Constraint Rule]
indexterm:[Constraint,Rule,score]
|score-attribute
|
|The node attribute to look up and use as a score if the rule
evaluates to +true+. Limited to use in rules that are part of
location constraints.
indexterm:[score-attribute,Constraint Rule]
indexterm:[Constraint,Rule,score-attribute]
|boolean-op
|+and+
|How to combine the result of multiple expression objects. Allowed
values are +and+ and +or+.
indexterm:[boolean-op,Constraint Rule]
indexterm:[Constraint,Rule,boolean-op]
|=========================================================
== Node Attribute Expressions ==
indexterm:[Resource,Constraint,Attribute Expression]
Expression objects are used to control a resource based on the
attributes defined by a node or nodes.
.Properties of an Expression
[width="95%",cols="1m,1,5<a",options="header",align="center"]
|=========================================================
|Field
|Default
|Description
|value
|
|User-supplied value for comparison
indexterm:[value,Constraint Expression]
indexterm:[Constraint,Attribute Expression,value]
|attribute
|
|The node attribute to test
indexterm:[attribute,Constraint Expression]
indexterm:[Constraint,Attribute Expression,attribute]
|type
|+string+
|Determines how the value(s) should be tested. Allowed values are
+string+, +integer+, and +version+.
indexterm:[type,Constraint Expression]
indexterm:[Constraint,Attribute Expression,type]
|operation
|
|The comparison to perform. Allowed values:
* +lt:+ True if the value of the node's +attribute+ is less than +value+
* +gt:+ True if the value of the node's +attribute+ is greater than +value+
* +lte:+ True if the value of the node's +attribute+ is less than or equal to +value+
* +gte:+ True if the value of the node's +attribute+ is greater than or equal to +value+
* +eq:+ True if the value of the node's +attribute+ is equal to +value+
* +ne:+ True if the value of the node's +attribute+ is not equal to +value+
* +defined:+ True if the node has the named attribute
* +not_defined:+ True if the node does not have the named attribute
indexterm:[operation,Constraint Expression]
indexterm:[Constraint,Attribute Expression,operation]
|=========================================================
In addition to any attributes added by the administrator, the cluster defines
special, built-in node attributes for each node that can also be used.
.Built-in node attributes
[width="95%",cols="1m,5<a",options="header",align="center"]
|=========================================================
|Name
|Value
|#uname
|Node name
|#kind
|Node type. Possible values are +cluster+, +remote+, and +container+. Kind is
+remote+ for Pacemaker Remote nodes created with the +ocf:pacemaker:remote+
resource, and +container+ for Pacemaker Remote guest nodes (a legacy name
unrelated to the now-common use of "container" for resource isolation).
'(since 1.1.13)'
|#ra-version
|The installed version of the resource agent on the node, as defined
by the +version+ attribute of the +resource-agent+ tag in the agent's
metadata. Valid only within rules controlling resource options. This can be
useful during rolling upgrades of a backward-incompatible resource agent.
'(coming in 1.1.16)'
|=========================================================
== Time- and Date-Based Expressions ==
indexterm:[Time Based Expressions]
indexterm:[Resource,Constraint,Date/Time Expression]
As the name suggests, +date_expressions+ are used to control a
resource or cluster option based on the current date/time. They may
contain an optional +date_spec+ and/or +duration+ object depending on
the context.
.Properties of a Date Expression
[width="95%",cols="2m,5<a",options="header",align="center"]
|=========================================================
|Field
|Description
|start
|A date/time conforming to the http://en.wikipedia.org/wiki/ISO_8601[ISO8601]
specification.
indexterm:[start,Constraint Expression]
indexterm:[Constraint,Date/Time Expression,start]
|end
|A date/time conforming to the http://en.wikipedia.org/wiki/ISO_8601[ISO8601]
specification. Can be inferred by supplying a value for +start+ and a
+duration+.
indexterm:[end,Constraint Expression]
indexterm:[Constraint,Date/Time Expression,end]
|operation
|Compares the current date/time with the start and/or end date,
depending on the context. Allowed values:
* +gt:+ True if the current date/time is after +start+
* +lt:+ True if the current date/time is before +end+
-* +in-range:+ True if the current date/time is after +start+ and before +end+
-* +date-spec:+ True if the current date/time matches a +date_spec+ object
+* +in_range:+ True if the current date/time is after +start+ and before +end+
+* +date_spec:+ True if the current date/time matches a +date_spec+ object
(described below)
indexterm:[operation,Constraint Expression]
indexterm:[Constraint,Date/Time Expression,operation]
|=========================================================
[NOTE]
======
As these comparisons (except for +date_spec+) include the time, the
+eq+, +neq+, +gte+ and +lte+ operators have not been implemented since
they would only be valid for a single second.
======
=== Date Specifications ===
indexterm:[Date Specification]
indexterm:[Resource,Constraint,Date Specification]
+date_spec+ objects are used to create cron-like expressions relating
to time. Each field can contain a single number or a single range.
Instead of defaulting to zero, any field not supplied is ignored.
For example, +monthdays="1"+ matches the first day of every month and
+hours="09-17"+ matches the hours between 9am and 5pm (inclusive).
At this time, multiple ranges (e.g. +weekdays="1,2"+ or
+weekdays="1-2,5-6"+) are not supported; depending on
demand, this might be implemented in a future release.
.Properties of a Date Specification
[width="95%",cols="2m,5<",options="header",align="center"]
|=========================================================
|Field
|Description
|id
|A unique name for the object
indexterm:[id,Date Specification]
indexterm:[Constraint,Date Specification,id]
|hours
|Allowed values: 0-23
indexterm:[hours,Date Specification]
indexterm:[Constraint,Date Specification,hours]
|monthdays
|Allowed values: 1-31 (depending on month and year)
indexterm:[monthdays,Date Specification]
indexterm:[Constraint,Date Specification,monthdays]
|weekdays
|Allowed values: 1-7 (1=Monday, 7=Sunday)
indexterm:[weekdays,Date Specification]
indexterm:[Constraint,Date Specification,weekdays]
|yeardays
|Allowed values: 1-366 (depending on the year)
indexterm:[yeardays,Date Specification]
indexterm:[Constraint,Date Specification,yeardays]
|months
|Allowed values: 1-12
indexterm:[months,Date Specification]
indexterm:[Constraint,Date Specification,months]
|weeks
|Allowed values: 1-53 (depending on weekyear)
indexterm:[weeks,Date Specification]
indexterm:[Constraint,Date Specification,weeks]
|years
|Year according to the Gregorian calendar
indexterm:[years,Date Specification]
indexterm:[Constraint,Date Specification,years]
|weekyears
|Year in which the week started; e.g. 1 January 2005
can be specified as '2005-001 Ordinal', '2005-01-01 Gregorian' or '2004-W53-6
Weekly' and thus would match +years="2005"+ or +weekyears="2004"+
indexterm:[weekyears,Date Specification]
indexterm:[Constraint,Date Specification,weekyears]
|moon
|Allowed values are 0-7 (0 is new, 4 is full moon). Seriously, you can
use this. This was implemented to demonstrate the ease with which new
comparisons could be added.
indexterm:[moon,Date Specification]
indexterm:[Constraint,Date Specification,moon]
|=========================================================
=== Durations ===
indexterm:[Duration]
indexterm:[Resource,Constraint,Duration]
Durations are used to calculate a value for +end+ when one is not
-supplied to +in-range+ operations. They contain the same fields as
+supplied to +in_range+ operations. They contain the same fields as
+date_spec+ objects but without the limitations (e.g. you can have a
duration of 19 months). As with +date_specs+, any field not supplied is
ignored.
=== Sample Time-Based Expressions ===
A small sample of how time-based expressions can be used:
////
On older versions of asciidoc, the [source] directive makes the title disappear
////
.True if now is any time in the year 2005
====
[source,XML]
----
<rule id="rule1">
<date_expression id="date_expr1" start="2005-001" operation="in_range">
<duration years="1"/>
</date_expression>
</rule>
----
====
.Equivalent expression
====
[source,XML]
----
<rule id="rule2">
<date_expression id="date_expr2" operation="date_spec">
<date_spec years="2005"/>
</date_expression>
</rule>
----
====
.9am-5pm Monday-Friday
====
[source,XML]
-------
<rule id="rule3">
<date_expression id="date_expr3" operation="date_spec">
<date_spec hours="9-16" days="1-5"/>
</date_expression>
</rule>
-------
====
Please note that the +16+ matches up to +16:59:59+, as the numeric
value (hour) still matches!
.9am-6pm Monday through Friday or anytime Saturday
====
[source,XML]
-------
<rule id="rule4" boolean_op="or">
<date_expression id="date_expr4-1" operation="date_spec">
<date_spec hours="9-16" days="1-5"/>
</date_expression>
<date_expression id="date_expr4-2" operation="date_spec">
<date_spec days="6"/>
</date_expression>
</rule>
-------
====
.9am-5pm or 9pm-12am Monday through Friday
====
[source,XML]
-------
<rule id="rule5" boolean_op="and">
<rule id="rule5-nested1" boolean_op="or">
<date_expression id="date_expr5-1" operation="date_spec">
<date_spec hours="9-16"/>
</date_expression>
<date_expression id="date_expr5-2" operation="date_spec">
<date_spec hours="21-23"/>
</date_expression>
</rule>
<date_expression id="date_expr5-3" operation="date_spec">
<date_spec days="1-5"/>
</date_expression>
</rule>
-------
====
.Mondays in March 2005
====
[source,XML]
-------
<rule id="rule6" boolean_op="and">
<date_expression id="date_expr6-1" operation="date_spec">
<date_spec weekdays="1"/>
</date_expression>
<date_expression id="date_expr6-2" operation="in_range"
start="2005-03-01" end="2005-04-01"/>
</rule>
-------
====
[NOTE]
======
Because no time is specified with the above dates, 00:00:00 is implied. This
means that the range includes all of 2005-03-01 but none of 2005-04-01.
You may wish to write +end="2005-03-31T23:59:59"+ to avoid confusion.
======
.A full moon on Friday the 13th
=====
[source,XML]
-------
<rule id="rule7" boolean_op="and">
<date_expression id="date_expr7" operation="date_spec">
<date_spec weekdays="5" monthdays="13" moon="4"/>
</date_expression>
</rule>
-------
=====
== Using Rules to Determine Resource Location ==
indexterm:[Rule,Determine Resource Location]
indexterm:[Resource,Location,Determine by Rules]
A location constraint may contain rules. When the constraint's outermost
rule evaluates to +false+, the cluster treats the constraint as if it were not
there. When the rule evaluates to +true+, the node's preference for running
the resource is updated with the score associated with the rule.
If this sounds familiar, it is because you have been using a simplified
syntax for location constraint rules already. Consider the following
location constraint:
.Prevent myApacheRsc from running on c001n03
=====
[source,XML]
-------
<rsc_location id="dont-run-apache-on-c001n03" rsc="myApacheRsc"
score="-INFINITY" node="c001n03"/>
-------
=====
This constraint can be more verbosely written as:
.Prevent myApacheRsc from running on c001n03 - expanded version
=====
[source,XML]
-------
<rsc_location id="dont-run-apache-on-c001n03" rsc="myApacheRsc">
<rule id="dont-run-apache-rule" score="-INFINITY">
<expression id="dont-run-apache-expr" attribute="#uname"
operation="eq" value="c00n03"/>
</rule>
</rsc_location>
-------
=====
The advantage of using the expanded form is that one can then add
extra clauses to the rule, such as limiting the rule such that it only
applies during certain times of the day or days of the week.
=== Location Rules Based on Other Node Properties ===
The expanded form allows us to match on node properties other than its name.
If we rated each machine's CPU power such that the cluster had the
following nodes section:
.A sample nodes section for use with score-attribute
=====
[source,XML]
-------
<nodes>
<node id="uuid1" uname="c001n01" type="normal">
<instance_attributes id="uuid1-custom_attrs">
<nvpair id="uuid1-cpu_mips" name="cpu_mips" value="1234"/>
</instance_attributes>
</node>
<node id="uuid2" uname="c001n02" type="normal">
<instance_attributes id="uuid2-custom_attrs">
<nvpair id="uuid2-cpu_mips" name="cpu_mips" value="5678"/>
</instance_attributes>
</node>
</nodes>
-------
=====
then we could prevent resources from running on underpowered machines with this rule:
[source,XML]
-------
<rule id="need-more-power-rule" score="-INFINITY">
<expression id="need-more-power-expr" attribute="cpu_mips"
operation="lt" value="3000"/>
</rule>
-------
=== Using +score-attribute+ Instead of +score+ ===
When using +score-attribute+ instead of +score+, each node matched by
the rule has its score adjusted differently, according to its value
for the named node attribute. Thus, in the previous example, if a
rule used +score-attribute="cpu_mips"+, +c001n01+ would have its
preference to run the resource increased by +1234+ whereas +c001n02+
would have its preference increased by +5678+.
== Using Rules to Control Resource Options ==
Often some cluster nodes will be different from their peers. Sometimes,
these differences -- e.g. the location of a binary or the names of network
interfaces -- require resources to be configured differently depending
on the machine they're hosted on.
By defining multiple +instance_attributes+ objects for the resource
and adding a rule to each, we can easily handle these special cases.
In the example below, +mySpecialRsc+ will use eth1 and port 9999 when
run on +node1+, eth2 and port 8888 on +node2+ and default to eth0 and
port 9999 for all other nodes.
.Defining different resource options based on the node name
=====
[source,XML]
-------
<primitive id="mySpecialRsc" class="ocf" type="Special" provider="me">
<instance_attributes id="special-node1" score="3">
<rule id="node1-special-case" score="INFINITY" >
<expression id="node1-special-case-expr" attribute="#uname"
operation="eq" value="node1"/>
</rule>
<nvpair id="node1-interface" name="interface" value="eth1"/>
</instance_attributes>
<instance_attributes id="special-node2" score="2" >
<rule id="node2-special-case" score="INFINITY">
<expression id="node2-special-case-expr" attribute="#uname"
operation="eq" value="node2"/>
</rule>
<nvpair id="node2-interface" name="interface" value="eth2"/>
<nvpair id="node2-port" name="port" value="8888"/>
</instance_attributes>
<instance_attributes id="defaults" score="1" >
<nvpair id="default-interface" name="interface" value="eth0"/>
<nvpair id="default-port" name="port" value="9999"/>
</instance_attributes>
</primitive>
-------
=====
The order in which +instance_attributes+ objects are evaluated is
determined by their score (highest to lowest). If not supplied, score
defaults to zero, and objects with an equal score are processed in
listed order. If the +instance_attributes+ object has no rule
or a +rule+ that evaluates to +true+, then for any parameter the resource does
not yet have a value for, the resource will use the parameter values defined by
the +instance_attributes+.
For example, given the configuration above, if the resource is placed on node1:
. +special-node1+ has the highest score (3) and so is evaluated first;
its rule evaluates to +true+, so +interface+ is set to +eth1+.
. +special-node2+ is evaluated next with score 2, but its rule evaluates to +false+,
so it is ignored.
. +defaults+ is evaluated last with score 1, and has no rule, so its values
are examined; +interface+ is already defined, so the value here is not used,
but +port+ is not yet defined, so +port+ is set to +9999+.
== Using Rules to Control Cluster Options ==
indexterm:[Rule,Controlling Cluster Options]
indexterm:[Cluster,Setting Options with Rules]
Controlling cluster options is achieved in much the same manner as
specifying different resource options on different nodes.
The difference is that because they are cluster options, one cannot
(or should not, because they won't work) use attribute-based
expressions. The following example illustrates how to set a different
+resource-stickiness+ value during and outside work hours. This
allows resources to automatically move back to their most preferred
hosts, but at a time that (in theory) does not interfere with business
activities.
.Change +resource-stickiness+ during working hours
=====
[source,XML]
-------
<rsc_defaults>
<meta_attributes id="core-hours" score="2">
<rule id="core-hour-rule" score="0">
<date_expression id="nine-to-five-Mon-to-Fri" operation="date_spec">
<date_spec id="nine-to-five-Mon-to-Fri-spec" hours="9-16" weekdays="1-5"/>
</date_expression>
</rule>
<nvpair id="core-stickiness" name="resource-stickiness" value="INFINITY"/>
</meta_attributes>
<meta_attributes id="after-hours" score="1" >
<nvpair id="after-stickiness" name="resource-stickiness" value="0"/>
</meta_attributes>
</rsc_defaults>
-------
=====
[[s-rules-recheck]]
== Ensuring Time-Based Rules Take Effect ==
A Pacemaker cluster is an event-driven system. As such, it won't
recalculate the best place for resources to run unless something
(like a resource failure or configuration change) happens. This can
mean that a location constraint that only allows resource X to run
between 9am and 5pm is not enforced.
If you rely on time-based rules, the +cluster-recheck-interval+ cluster option
(which defaults to 15 minutes) is essential. This tells the cluster to
periodically recalculate the ideal state of the cluster.
For example, if you set +cluster-recheck-interval="5m"+, then sometime between
09:00 and 09:05 the cluster would notice that it needs to start resource X,
and between 17:00 and 17:05 it would realize that X needed to be stopped.
The timing of the actual start and stop actions depends on what other actions
the cluster may need to perform first.

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