Chapter 12. High availability and clusters
The following chapter contains the most notable changes to high availability and clusters between RHEL 9 and RHEL 10.
Support for the RHEL Resilient Storage Add-On has been removed
The Red Hat Enterprise Linux (RHEL) Resilient Storage Add-On will no longer be supported starting with Red Hat Enterprise Linux 10 and any subsequent releases after RHEL 10. The RHEL Resilient Storage Add-On will continue to be supported with earlier versions of RHEL (7, 8, 9) and throughout their respective maintenance support lifecycles.
pcsd
Web UI no longer available as a standalone user interface
The pcsd
Web UI is now available as the HA Cluster Management RHEL web console add-on when the cockpit-ha-cluster
package is installed. It is no longer operated as a standalone interface.
Removed functionality for the Red Hat High Availability Add-On
The following Red Hat High Availability Add-On features are no longer supported in RHEL 10.
- RKT containers in bundles. Docker and Podman containers are still supported.
-
The
upstart
andnagios
resource classes. -
Location constraints with multiple top-level rules. Only one rule per constraint is allowed. The
pcs constraint rule add
,pcs constraint rule delete
and thepcs constraint rule remove
commands have been removed. If you have configured constraints with multiple rules, run thepcs cluster cib-upgrade
command to update to the latest CIB schema. During the update, Pacemaker creates a constraint for each rule, so that there will be only one rule in each constraint. -
The
monthdays
,moon
,weekdays
,weekyears
, andyearsdays
duration options for Pacemaker rules. - Using spaces in dates in location constraint rules.
-
Delimiting stonith devices with a comma in
pcs stonith level add | clear | delete | remove
commands. -
Ambiguous syntax of the
pcs stonith level clear | delete | remove
command. The commnd has been clarified to distinguish a target from a stonith device. -
The legacy role names of
master
andslave
are no longer accepted by thepcs
command-line interface. UsePromoted
,Unpromoted
, --promoted,promotable
, andpromoted-max
instead. -
Using stonith resources in
pcs resource
commands and resources inpcs stonith
commands, as well as--brief
,--no-strict
,--safe
and--simulate
flags of thepcs stonith disable
command -
Ability to create a stonith resource in a group with the
pcs stonith create
command -
The
stonith.create_in_group
command from API v1 and v2 -
The
pcs cluster pcsd-status
command. Use thepcs status pcsd
orpcs pcsd status
command. -
The
pcs cluster certkey
command. Use thepcs pcsd certkey
command. -
The
pcs resource | stonith [op] defaults <name>=<value>…
command. Use thepcs resource | stonith [op] defaults update
command. -
The
pcs acl show
command. Use thepcs acl config
command. -
The
pcs alert show
command. Use thepcs alert config
command. -
The
pcs constraint [location | colocation | order | ticket] show | list
commands. Use thepcs constraint [location | colocation | order | ticket] config
command. -
The
pcs property show
and thepcs property list
commands. Use thepcs property config
command. -
The
pcs tag list
command. Use thepcs tag config
command. -
The
--autodelete
flag of thepcs resource move
command.
Removed and updated Pacemaker CIB elements
The following configuration components of the Pacemaker CIB have been removed or modified in RHEL 10. When you upgrade to RHEL 10, these components are automatically removed, modified, or replaced as described. Before you upgrade, ensure that the Pacemaker CIB has a supported value for the validate-with
attribute. Although you should not edit the cluster configuration file directly, you can view the raw cluster configuration with the pcs cluster cib
command.
An upgrade modifies the following CIB components:
-
The
validate-with
attribute of thecib
element, which is set topacemaker-4.0
-
The
stonith-action
cluster property, which is set tooff
if it was previously set topoweroff
-
Legacy promotable clone (master) resources, which are changed to standard promotable clones by changing the
master
xml element to theclone
xml element and by setting thepromotable
meta attribute - Location constraints with more than one top-level rule, which are converted to separate location constraints for each top-level rule
An upgrade renames the following components:
-
The
crmd-finalization-timeout
cluster property, which is renamed tojoin-finalization-timeout
-
The
crmd-integration-timeout
cluster property, which is renamed tojoin-integration-timeout
-
The
crmd-transition-delay
cluster property, which is renamed totransition-delay
An upgrade removes the following components from the CIB:
-
nagios-class
andupstart-class
resources -
bundle
resources based on anrkt
container. -
The
restart-type
resource meta-attribute -
The
can_fail
operation meta-attribute -
The
role_after_failure
operationmeta-attribute
-
moon
attributes indate_spec
elements of rules -
The
remove-after-stop
cluster property. - Ping nodes, which are changed to cluster member nodes with all resources banned and probes disabled
- NVpairs without a value attribute
- Duplicate NVpairs with a given name within an NVset, for which only the first NVpair is kept
An upgrade changes the following default values:
- An action configured as a fence device parameter is now ignored rather than treated as a default fencing action.
-
The
concurrent-fencing
cluster option now defaults totrue
and is deprecated. -
The
globally-unique
clone option now defaults totrue
whenclone-node-max
is greater than 1.
An upgrade removes lifetime
elements, and modifies the CIB as follows:
lifetime
elements in a location constraint are removed.-
If the
lifetime
element in a location constraint has no top-level rules, thelifetime
-based rule becomes the constraint’s top-level rule. -
If the
lifetime
element in a location constraint has multiple top-level rules, they are nested inside a singleor
rule. -
If the
lifetime
element in a location constraint has a single top-level rule, a new and top-level constraint rule is added that contains the existing top-level constraint rule and thelifetime
-based rule.
-
If the
-
lifetime
elements in a colocation or order constraint are removed. If any rules contained in the colocation or order constraint are referenced elsewhere, they are put in a new location constraint that does not apply to any resources. They are put in a location constraint since a rule in alifetime
element may contain a node attribute expression, which is now allowed only within a location constraint rule. - Following an upgrade, invalid fencing levels display a warning when the CIB is loaded.