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 # Pacemaker Cluster Test Suite (CTS)
 
 The Cluster Test Suite (CTS) refers to all Pacemaker testing code that can be
 run in an installed environment. (Pacemaker also has unit tests that must be
 run from a source distribution.)
 
 CTS includes:
 
 * Regression tests: These test specific Pacemaker components individually (no
   integration tests). The primary front end is cts-regression in this
   directory. Run it with the --help option to see its usage.
 
   cts-regression is a wrapper for individual component regression tests also
   in this directory (cts-cli, cts-exec, cts-fencing, and cts-scheduler).
 
   The CLI and scheduler regression tests can also be run from a source
   distribution. The other regression tests can only run in an installed
   environment, and the cluster should not be running on the node running these
   tests.
 
 * The CTS lab: This is a cluster exerciser for intensively testing the behavior
   of an entire working cluster. It is primarily for developers and packagers of
   the Pacemaker source code, but it can be useful for users who wish to see how
   their cluster will react to various situations. Most of the lab code is in
   the Pacemaker Python module. The front end, cts-lab, is in this directory.
 
   The CTS lab runs a randomized series of predefined tests on the cluster. It
   can be run against a pre-existing cluster configuration or overwrite the
   existing configuration with a test configuration.
 
 * Helpers: Some of the component regression tests and the CTS lab require
   certain helpers to be installed as root. These include a dummy LSB init
   script, dummy systemd service, etc. In a source distribution, the source for
   these is in cts/support.
 
   The tests will install these as needed and uninstall them when done. This
   means that the cluster configuration created by the CTS lab will generate
   failures if started manually after the lab exits. However, the helper
   installer can be run manually to make the configuration usable, if you want
   to do your own further testing with it:
 
       /usr/libexec/pacemaker/cts-support install
 
   As you might expect, you can also remove the helpers with:
 
       /usr/libexec/pacemaker/cts-support uninstall
 
   (The actual directory location may vary depending on how Pacemaker was
   built.)
 
 * Cluster benchmark: The benchmark subdirectory of this directory contains some
   cluster test environment benchmarking code. It is not particularly useful for
   end users.
 
 * Valgrind suppressions: When memory-testing Pacemaker code with valgrind,
   various bugs in non-Pacemaker libraries and such can clutter the results. The
   valgrind-pcmk.suppressions file in this directory can be used with valgrind's
   --suppressions option to eliminate many of these.
 
 
 ## Using the CTS lab
 
 ### Requirements
 
 * Three or more machines (one test exerciser and at least two cluster nodes).
 
 * The test cluster nodes should be on the same subnet and have journalling
   filesystems (ext4, xfs, etc.) for all of their filesystems other than
   /boot. You also need a number of free IP addresses on that subnet if you
   intend to test IP address takeover.
 
 * The test exerciser machine doesn't need to be on the same subnet as the test
   cluster machines. Minimal demands are made on the exerciser; it just has to
   stay up during the tests.
 
 * Tracking problems is easier if all machines' clocks are closely synchronized.
   NTP does this automatically, but you can do it by hand if you want.
 
 * The account on the exerciser used to run the CTS lab (which does not need to
   be root) must be able to ssh as root to the cluster nodes without a password
   challenge. See the Mini-HOWTO at the end of this file for details about how
   to configure ssh for this.
 
 * The exerciser needs to be able to resolve all cluster node names, whether by
   DNS or /etc/hosts.
 
 * CTS is not guaranteed to run on all platforms that Pacemaker itself does.
   It calls commands such as service that may not be provided by all OSes.
 
 
 ### Preparation
 
 * Install Pacemaker, including the testing code, on all machines. The testing
   code must be the same version as the rest of Pacemaker, and the Pacemaker
   version must be the same on the exerciser and all cluster nodes.
 
   You can install from source, although many distributions package the testing
   code (named pacemaker-cts or similar). Typically, everything needed by the
   CTS lab is installed in /usr/share/pacemaker/tests/cts.
 
 * Configure the cluster layer (Corosync) on the cluster machines (*not* the
   exerciser), and verify it works. Node names used in the cluster configuration
   *must* match the hosts' names as returned by `uname -n`; they do not have to
   match the machines' fully qualified domain names.
 
+* Optionally, configure the exerciser as a log aggregator, using something like
+  `rsyslog` log forwarding. If aggregation is detected, the exerciser will look
+  for new messages locally instead of requesting them repeatedly from cluster
+  nodes.
+  * Currently, `/var/log/messages` on the exerciser is the only supported log
+    destination. Further, if it's specified explicitly on the command line as
+    the log file, then CTS lab will not check for aggregation.
+  * CTS lab does not currently detect systemd journal log aggregation.
+
 
 ### Run
 
 The primary interface to the CTS lab is the cts-lab executable:
 
     /usr/share/pacemaker/tests/cts-lab [options] <number-of-tests-to-run>
 
 (The actual directory location may vary depending on how Pacemaker was built.)
 
 As part of the options, specify the cluster nodes with --nodes, for example:
 
     --nodes "pcmk-1 pcmk-2 pcmk-3"
 
 Most people will want to save the output to a file, for example:
 
     --outputfile ~/cts.log
 
 Unless you want to test a pre-existing cluster configuration, you also want
 (*warning*: with these options, any existing configuration will be lost):
 
     --clobber-cib
     --populate-resources
 
 You can test floating IP addresses (*not* already used by any host), one per
 cluster node, by specifying the first, for example:
 
     --test-ip-base 192.168.9.100
 
 Configure some sort of fencing, for example to use fence\_xvm:
 
     --stonith xvm
 
 Putting all the above together, a command line might look like:
 
     /usr/share/pacemaker/tests/cts-lab --nodes "pcmk-1 pcmk-2 pcmk-3" \
         --outputfile ~/cts.log --clobber-cib --populate-resources \
         --test-ip-base 192.168.9.100 --stonith xvm 50
 
 For more options, run with the --help option.
 
 There are also a couple of wrappers for cts-lab that some users may find more
 convenient: cts, which is typically installed in the same place as the rest of
 the testing code; and cluster\_test, which is in the source directory and
 typically not installed.
 
 To extract the result of a particular test, run:
 
     crm_report -T $test
 
 
 ### Optional: Memory testing
 
 Pacemaker has various options for testing memory management. On cluster nodes,
 Pacemaker components use various environment variables to control these
 options. How these variables are set varies by OS, but usually they are set in
 a file such as /etc/sysconfig/pacemaker or /etc/default/pacemaker.
 
 Valgrind is a program for detecting memory management problems such as
 use-after-free errors. If you have valgrind installed, you can enable it by
 setting the following environment variables on all cluster nodes:
 
     PCMK_valgrind_enabled=pacemaker-attrd,pacemaker-based,pacemaker-controld,pacemaker-execd,pacemaker-fenced,pacemaker-schedulerd
     VALGRIND_OPTS="--leak-check=full --trace-children=no --num-callers=25
         --log-file=/var/lib/pacemaker/valgrind-%p
         --suppressions=/usr/share/pacemaker/tests/valgrind-pcmk.suppressions
         --gen-suppressions=all"
 
 If running the CTS lab with valgrind enabled on the cluster nodes, add these
 options to cts-lab:
 
     --valgrind-tests --valgrind-procs "pacemaker-attrd pacemaker-based pacemaker-controld pacemaker-execd pacemaker-schedulerd pacemaker-fenced"
 
 These options should only be set while specifically testing memory management,
 because they may slow down the cluster significantly, and they will disable
 writes to the CIB. If desired, you can enable valgrind on a subset of pacemaker
 components rather than all of them as listed above.
 
 Valgrind will put a text file for each process in the location specified by
 valgrind's --log-file option. See
 https://www.valgrind.org/docs/manual/mc-manual.html for explanations of the
 messages valgrind generates.
 
 Separately, if you are using the GNU C library, the G\_SLICE,
 MALLOC\_PERTURB\_, and MALLOC\_CHECK\_ environment variables can be set to
 affect the library's memory management functions.
 
 When using valgrind, G\_SLICE should be set to "always-malloc", which helps
 valgrind track memory by always using the malloc() and free() routines
 directly. When not using valgrind, G\_SLICE can be left unset, or set to
 "debug-blocks", which enables the C library to catch many memory errors
 but may impact performance.
 
 If the MALLOC\_PERTURB\_ environment variable is set to an 8-bit integer, the C
 library will initialize all newly allocated bytes of memory to the integer
 value, and will set all newly freed bytes of memory to the bitwise inverse of
 the integer value. This helps catch uses of uninitialized or freed memory
 blocks that might otherwise go unnoticed. Example:
 
     MALLOC_PERTURB_=221
 
 If the MALLOC\_CHECK\_ environment variable is set, the C library will check for
 certain heap corruption errors. The most useful value in testing is 3, which
 will cause the library to print a message to stderr and abort execution.
 Example:
 
     MALLOC_CHECK_=3
 
 Valgrind should be enabled for either all nodes or none when used with the CTS
 lab, but the C library variables may be set differently on different nodes.
 
 
 ### Optional: Remote node testing
 
 If the pacemaker-remoted daemon is installed on all cluster nodes, the CTS lab
 will enable remote node tests.
 
 The remote node tests choose a random node, stop the cluster on it, start
 pacemaker-remoted on it, and add an ocf:pacemaker:remote resource to turn it
 into a remote node. When the test is done, the lab will turn the node back into
 a cluster node.
 
 To avoid conflicts, the lab will rename the node, prefixing the original node
 name with "remote-". For example, "pcmk-1" will become "remote-pcmk-1". These
 names do not need to be resolvable.
 
 The name change may require special fencing configuration, if the fence agent
 expects the node name to be the same as its hostname. A common approach is to
 specify the "remote-" names in pcmk\_host\_list. If you use
 pcmk\_host\_list=all, the lab will expand that to all cluster nodes and their
 "remote-" names.  You may additionally need a pcmk\_host\_map argument to map
 the "remote-" names to the hostnames. Example:
 
     --stonith xvm --stonith-args \
     pcmk_host_list=all,pcmk_host_map=remote-pcmk-1:pcmk-1;remote-pcmk-2:pcmk-2
 
 
 ### Optional: Remote node testing with valgrind
 
 When running the remote node tests, the Pacemaker components on the *cluster*
 nodes can be run under valgrind as described in the "Memory testing" section.
 However, pacemaker-remoted cannot be run under valgrind that way, because it is
 started by the OS's regular boot system and not by Pacemaker.
 
 Details vary by system, but the goal is to set the VALGRIND\_OPTS environment
 variable and then start pacemaker-remoted by prefixing it with the path to
 valgrind.
 
 The init script and systemd service file provided with pacemaker-remoted will
 load the pacemaker environment variables from the same location used by other
 Pacemaker components, so VALGRIND\_OPTS will be set correctly if using one of
 those.
 
 For an OS using systemd, you can override the ExecStart parameter to run
 valgrind. For example:
 
     mkdir /etc/systemd/system/pacemaker_remote.service.d
     cat >/etc/systemd/system/pacemaker_remote.service.d/valgrind.conf <<EOF
     [Service]
     ExecStart=
     ExecStart=/usr/bin/valgrind /usr/sbin/pacemaker-remoted
     EOF
 
 
 ### Mini-HOWTO: Allow passwordless remote SSH connections
 
 The CTS lab runs "ssh -l root" so you don't have to do any of your testing
 logged in as root on the exerciser. Here is how to allow such connections
 without requiring a password to be entered each time:
 
 * On your test exerciser, create an SSH key if you do not already have one.
   Most commonly, SSH keys will be in your ~/.ssh directory, with the
   private key file not having an extension, and the public key file
   named the same with the extension ".pub" (for example, ~/.ssh/id\_rsa.pub).
 
   If you don't already have a key, you can create one with:
 
       ssh-keygen -t rsa
 
 * From your test exerciser, authorize your SSH public key for root on all test
   machines (both the exerciser and the cluster test machines):
 
       ssh-copy-id -i ~/.ssh/id_rsa.pub root@$MACHINE
 
   You will probably have to provide your password, and possibly say
   "yes" to some questions about accepting the identity of the test machines.
 
   The above assumes you have a RSA SSH key in the specified location;
   if you have some other type of key (DSA, ECDSA, etc.), use its file name
   in the -i option above.
 
 * To verify, try this command from the exerciser machine for each
   of your cluster machines, and for the exerciser machine itself.
 
       ssh -l root $MACHINE
 
   If this works without prompting for a password, you're in business.
   If not, look at the documentation for your version of ssh.
 
 
 ## Upgrading scheduler test inputs for new XSLTs
 
 The scheduler/xml inputs should be kept in sync with the latest major schema
 version, since these tests are not meant to test schema upgrades (unless
 expressly designated as such).
 
 To upgrade the inputs to a new major schema version:
 
     cd "$(git rev-parse --show-toplevel)/xml"
     ./regression.sh cts_scheduler -G
     cd "$(git rev-parse --show-toplevel)/cts"
     git add --interactive .
     git commit -m 'Test: scheduler: upgrade test inputs to schema $X.$Y'
     ./cts-scheduler || echo 'Investigate what went wrong'
 
 The first two commands can be run anytime to verify no further upgrades are
 needed.