9. Glossary
- assign
- In the scheduler, this refers to associating a resource with a node. Do
not use allocate for this purpose.
- bundle
- The collective resource type associating instances of a container with
storage and networking. Do not use container when referring to
the bundle as a whole.
- cluster layer
- The layer of the cluster stack that provides membership and
messaging capabilities (such as Corosync).
- cluster stack
- The core components of a high-availability cluster: the
cluster layer at the “bottom” of the stack, then Pacemaker, then
resource agents, and then the actual services managed by the cluster at
the “top” of the stack. Do not use stack for the cluster layer alone.
- CPG
- Corosync Process Group. This is the messaging layer in a Corosync-based
cluster. Pacemaker daemons use CPG to communicate with their counterparts
on other nodes.
- container
- This can mean either a container in the usual sense (whether as a
standalone resource or as part of a bundle), or as the container resource
meta-attribute (which does not necessarily reference a container in the
usual sense).
- dangling migration
- Live migration of a resource consists of a migrate_to action on the
source node, followed by a migrate_from on the target node, followed
by a stop on the source node. If the migrate_to and
migrate_from have completed successfully, but the stop has not
yet been done, the migration is considered to be dangling.
- dependent
- In colocation constraints, this refers to the resource located relative
to the primary resource. Do not use rh or right-hand for this
purpose.
- IPC
- Inter-process communication. In Pacemaker, clients send requests to
daemons using libqb IPC.
- message
- This can refer to log messages, custom messages defined for a
pcmk_output_t object, or XML messages sent via CPG or
IPC.
- metadata
- In the context of options and resource agents, this refers to OCF-style
metadata. Do not use a hyphen except when referring to the OCF-defined
action name meta-data.
- primary
- In colocation constraints, this refers to the resource that the
dependent resource is located relative to. Do not use lh or
left-hand for this purpose.
- primitive
- The fundamental resource type in Pacemaker. Do not use native for this
purpose.
- score
- An integer value constrained between -PCMK_SCORE_INFINITY and
+PCMK_SCORE_INFINITY. Certain strings (such as
PCMK_VALUE_INFINITY) parse as particular score values. Do not use
weight for this purpose.
- self-fencing
- When a node is chosen to execute its own fencing. Do not use suicide
for this purpose.