diff --git a/doc/sphinx/Pacemaker_Explained/cluster-options.rst b/doc/sphinx/Pacemaker_Explained/cluster-options.rst index 7848b2a876..6ebe5f38eb 100644 --- a/doc/sphinx/Pacemaker_Explained/cluster-options.rst +++ b/doc/sphinx/Pacemaker_Explained/cluster-options.rst @@ -1,932 +1,936 @@ Cluster-Wide Configuration -------------------------- .. index:: pair: XML element; cib pair: XML element; configuration Configuration Layout #################### The cluster is defined by the Cluster Information Base (CIB), which uses XML notation. The simplest CIB, an empty one, looks like this: .. topic:: An empty configuration .. code-block:: xml The empty configuration above contains the major sections that make up a CIB: * ``cib``: The entire CIB is enclosed with a ``cib`` element. Certain fundamental settings are defined as attributes of this element. * ``configuration``: This section -- the primary focus of this document -- contains traditional configuration information such as what resources the cluster serves and the relationships among them. * ``crm_config``: cluster-wide configuration options * ``nodes``: the machines that host the cluster * ``resources``: the services run by the cluster * ``constraints``: indications of how resources should be placed * ``status``: This section contains the history of each resource on each node. Based on this data, the cluster can construct the complete current state of the cluster. The authoritative source for this section is the local executor (pacemaker-execd process) on each cluster node, and the cluster will occasionally repopulate the entire section. For this reason, it is never written to disk, and administrators are advised against modifying it in any way. In this document, configuration settings will be described as properties or options based on how they are defined in the CIB: * Properties are XML attributes of an XML element. * Options are name-value pairs expressed as ``nvpair`` child elements of an XML element. Normally, you will use command-line tools that abstract the XML, so the distinction will be unimportant; both properties and options are cluster settings you can tweak. Options can appear within four types of enclosing elements: * ``cluster_property_set`` * ``instance_attributes`` * ``meta_attributes`` * ``utilization`` We will refer to a set of options and its enclosing element as a *block*. .. list-table:: **Properties of an Option Block's Enclosing Element** :class: longtable :widths: 2 2 3 5 :header-rows: 1 * - Name - Type - Default - Description * - .. _option_block_id: .. index:: pair: id; cluster_property_set pair: id; instance_attributes pair: id; meta_attributes pair: id; utilization single: attribute; id (cluster_property_set) single: attribute; id (instance_attributes) single: attribute; id (meta_attributes) single: attribute; id (utilization) id - :ref:`id ` - - A unique name for the block (required) * - .. _option_block_score: .. index:: pair: score; cluster_property_set pair: score; instance_attributes pair: score; meta_attributes pair: score; utilization single: attribute; score (cluster_property_set) single: attribute; score (instance_attributes) single: attribute; score (meta_attributes) single: attribute; score (utilization) score - :ref:`score ` - 0 - Priority with which to process the block Each block may optionally contain a :ref:`rule `. .. _option_precedence: Option Precedence ################# This subsection describes the precedence of options within a set of blocks and within a single block. Options are processed as follows: * All option blocks of a given type are processed in order of their ``score`` attribute, from highest to lowest. For ``cluster_property_set``, if there is a block whose enclosing element has ``id="cib-bootstrap-options"``, then that block is always processed first regardless of score. * If a block contains a rule that evaluates to false, that block is skipped. * Within a block, options are processed in order from first to last. * The first value found for a given option is applied, and the rest are ignored. Note that this means it is pointless to configure the same option twice in a single block, because occurrences after the first one would be ignored. For example, in the following configuration snippet, the ``no-quorum-policy`` value ``demote`` is applied. ``property-set2`` has a higher score than ``property-set1``, so it's processed first. There are no rules in this snippet, so both sets are processed. Within ``property-set2``, the value ``demote`` appears first, so the later value ``freeze`` is ignored. We've already found a value for ``no-quorum-policy`` before we begin processing ``property-set1``, so its value ``stop`` is ignored. .. code-block:: xml CIB Properties ############## Certain settings are defined by CIB properties (that is, attributes of the ``cib`` tag) rather than with the rest of the cluster configuration in the ``configuration`` section. The reason is simply a matter of parsing. These options are used by the configuration database which is, by design, mostly ignorant of the content it holds. So the decision was made to place them in an easy-to-find location. .. list-table:: **CIB Properties** :class: longtable :widths: 2 2 2 5 :header-rows: 1 * - Name - Type - Default - Description * - .. _admin_epoch: .. index:: pair: admin_epoch; cib admin_epoch - :ref:`nonnegative integer ` - 0 - When a node joins the cluster, the cluster asks the node with the highest (``admin_epoch``, ``epoch``, ``num_updates``) tuple to replace the configuration on all the nodes -- which makes setting them correctly very important. ``admin_epoch`` is never modified by the cluster; you can use this to make the configurations on any inactive nodes obsolete. * - .. _epoch: .. index:: pair: epoch; cib epoch - :ref:`nonnegative integer ` - 0 - The cluster increments this every time the CIB's configuration section is updated. * - .. _num_updates: .. index:: pair: num_updates; cib num_updates - :ref:`nonnegative integer ` - 0 - The cluster increments this every time the CIB's configuration or status sections are updated, and resets it to 0 when epoch changes. * - .. _validate_with: .. index:: pair: validate-with; cib validate-with - :ref:`enumeration ` - - Determines the type of XML validation that will be done on the configuration. Allowed values are ``none`` (in which case the cluster will not require that updates conform to expected syntax) and the base names of schema files installed on the local machine (for example, "pacemaker-3.9") * - .. _remote_tls_port: .. index:: pair: remote-tls-port; cib remote-tls-port - :ref:`port ` - - If set, the CIB manager will listen for anonymously encrypted remote connections on this port, to allow CIB administration from hosts not in the cluster. No key is used, so this should be used only on a protected network where man-in-the-middle attacks can be avoided. * - .. _remote_clear_port: .. index:: pair: remote-clear-port; cib remote-clear-port - :ref:`port ` - - If set to a TCP port number, the CIB manager will listen for remote connections on this port, to allow for CIB administration from hosts not in the cluster. No encryption is used, so this should be used only on a protected network. * - .. _cib_last_written: .. index:: pair: cib-last-written; cib cib-last-written - :ref:`date/time ` - - Indicates when the configuration was last written to disk. Maintained by the cluster; for informational purposes only. * - .. _have_quorum: .. index:: pair: have-quorum; cib have-quorum - :ref:`boolean ` - - Indicates whether the cluster has quorum. If false, the cluster's response is determined by ``no-quorum-policy`` (see below). Maintained by the cluster. * - .. _dc_uuid: .. index:: pair: dc-uuid; cib dc-uuid - :ref:`text ` - - Node ID of the cluster's current designated controller (DC). Used and maintained by the cluster. * - .. _execution_date: .. index:: pair: execution-date; cib execution-date - :ref:`epoch time ` - - Time to use when evaluating rules. .. _cluster_options: Cluster Options ############### Cluster options, as you might expect, control how the cluster behaves when confronted with various situations. They are grouped into sets within the ``crm_config`` section. In advanced configurations, there may be more than one set. (This will be described later in the chapter on :ref:`rules` where we will show how to have the cluster use different sets of options during working hours than during weekends.) For now, we will describe the simple case where each option is present at most once. You can obtain an up-to-date list of cluster options, including their default values, by running the ``man pacemaker-schedulerd`` and ``man pacemaker-controld`` commands. .. list-table:: **Cluster Options** :class: longtable :widths: 2 2 2 5 :header-rows: 1 * - Name - Type - Default - Description * - .. _cluster_name: .. index:: pair: cluster option; cluster-name cluster-name - :ref:`text ` - - An (optional) name for the cluster as a whole. This is mostly for users' convenience for use as desired in administration, but can be used in the Pacemaker configuration in :ref:`rules` (as the ``#cluster-name`` :ref:`node attribute `). It may also be used by higher-level tools when displaying cluster information, and by certain resource agents (for example, the ``ocf:heartbeat:GFS2`` agent stores the cluster name in filesystem meta-data). * - .. _dc_version: .. index:: pair: cluster option; dc-version dc-version - :ref:`version ` - *detected* - Version of Pacemaker on the cluster's designated controller (DC). Maintained by the cluster, and intended for diagnostic purposes. * - .. _cluster_infrastructure: .. index:: pair: cluster option; cluster-infrastructure cluster-infrastructure - :ref:`text ` - *detected* - The messaging layer with which Pacemaker is currently running. Maintained by the cluster, and intended for informational and diagnostic purposes. * - .. _no_quorum_policy: .. index:: pair: cluster option; no-quorum-policy no-quorum-policy - :ref:`enumeration ` - stop - What to do when the cluster does not have quorum. Allowed values: * ``ignore:`` continue all resource management * ``freeze:`` continue resource management, but don't recover resources from nodes not in the affected partition * ``stop:`` stop all resources in the affected cluster partition * ``demote:`` demote promotable resources and stop all other resources in the affected cluster partition *(since 2.0.5)* * ``fence:`` fence all nodes in the affected cluster partition *(since 2.1.9)* * ``suicide:`` same as ``fence`` *(deprecated since 2.1.9)* * - .. _batch_limit: .. index:: pair: cluster option; batch-limit batch-limit - :ref:`integer ` - 0 - The maximum number of actions that the cluster may execute in parallel across all nodes. The ideal value will depend on the speed and load of your network and cluster nodes. If zero, the cluster will impose a dynamically calculated limit only when any node has high load. If -1, the cluster will not impose any limit. * - .. _migration_limit: .. index:: pair: cluster option; migration-limit migration-limit - :ref:`integer ` - -1 - The number of :ref:`live migration ` actions that the cluster is allowed to execute in parallel on a node. A value of -1 means unlimited. * - .. _load_threshold: .. index:: pair: cluster option; load-threshold load-threshold - :ref:`percentage ` - 80% - Maximum amount of system load that should be used by cluster nodes. The cluster will slow down its recovery process when the amount of system resources used (currently CPU) approaches this limit. * - .. _node_action_limit: .. index:: pair: cluster option; node-action-limit node-action-limit - :ref:`integer ` - 0 - Maximum number of jobs that can be scheduled per node. If nonpositive or invalid, double the number of cores is used as the maximum number of jobs per node. :ref:`PCMK_node_action_limit ` overrides this option on a per-node basis. * - .. _symmetric_cluster: .. index:: pair: cluster option; symmetric-cluster symmetric-cluster - :ref:`boolean ` - true - If true, resources can run on any node by default. If false, a resource is allowed to run on a node only if a :ref:`location constraint ` enables it. * - .. _stop_all_resources: .. index:: pair: cluster option; stop-all-resources stop-all-resources - :ref:`boolean ` - false - Whether all resources should be disallowed from running (can be useful during maintenance or troubleshooting) * - .. _stop_orphan_resources: .. index:: pair: cluster option; stop-orphan-resources stop-orphan-resources - :ref:`boolean ` - true - Whether resources that have been deleted from the configuration should be stopped. This value takes precedence over :ref:`is-managed ` (that is, even unmanaged resources will be stopped when orphaned if this value is ``true``). * - .. _stop_orphan_actions: .. index:: pair: cluster option; stop-orphan-actions stop-orphan-actions - :ref:`boolean ` - true - Whether recurring :ref:`operations ` that have been deleted from the configuration should be cancelled * - .. _start_failure_is_fatal: .. index:: pair: cluster option; start-failure-is-fatal start-failure-is-fatal - :ref:`boolean ` - true - Whether a failure to start a resource on a particular node prevents further start attempts on that node. If ``false``, the cluster will decide whether the node is still eligible based on the resource's current failure count and ``migration-threshold``. * - .. _enable_startup_probes: .. index:: pair: cluster option; enable-startup-probes enable-startup-probes - :ref:`boolean ` - true - Whether the cluster should check the pre-existing state of resources when the cluster starts * - .. _maintenance_mode: .. index:: pair: cluster option; maintenance-mode maintenance-mode - :ref:`boolean ` - false - If true, the cluster will not start or stop any resource in the cluster, and any recurring operations (expect those specifying ``role`` as ``Stopped``) will be paused. If true, this overrides the :ref:`maintenance ` node attribute, :ref:`is-managed ` and :ref:`maintenance ` resource meta-attributes, and :ref:`enabled ` operation meta-attribute. * - .. _stonith_enabled: .. index:: pair: cluster option; stonith-enabled stonith-enabled - :ref:`boolean ` - true - Whether the cluster is allowed to fence nodes (for example, failed nodes and nodes with resources that can't be stopped). If true, at least one fence device must be configured before resources are allowed to run. If false, unresponsive nodes are immediately assumed to be running no resources, and resource recovery on online nodes starts without any further protection (which can mean *data loss* if the unresponsive node still accesses shared storage, for example). See also the :ref:`requires ` resource meta-attribute. + + This option applies only to fencing scheduled by the cluster, not to + requests initiated externally (such as with the ``stonith_admin`` + command-line tool). * - .. _stonith_action: .. index:: pair: cluster option; stonith-action stonith-action - :ref:`enumeration ` - reboot - Action the cluster should send to the fence agent when a node must be fenced. Allowed values are ``reboot`` and ``off``. * - .. _stonith_timeout: .. index:: pair: cluster option; stonith-timeout stonith-timeout - :ref:`duration ` - 60s - How long to wait for ``on``, ``off``, and ``reboot`` fence actions to complete by default. * - .. _stonith_max_attempts: .. index:: pair: cluster option; stonith-max-attempts stonith-max-attempts - :ref:`score ` - 10 - How many times fencing can fail for a target before the cluster will no longer immediately re-attempt it. Any value below 1 will be ignored, and the default will be used instead. * - .. _have_watchdog: .. index:: pair: cluster option; have-watchdog have-watchdog - :ref:`boolean ` - *detected* - Whether watchdog integration is enabled. This is set automatically by the cluster according to whether SBD is detected to be in use. User-configured values are ignored. The value `true` is meaningful if diskless SBD is used and :ref:`stonith-watchdog-timeout ` is nonzero. In that case, if fencing is required, watchdog-based self-fencing will be performed via SBD without requiring a fencing resource explicitly configured. * - .. _stonith_watchdog_timeout: .. index:: pair: cluster option; stonith-watchdog-timeout stonith-watchdog-timeout - :ref:`timeout ` - 0 - If nonzero, and the cluster detects ``have-watchdog`` as ``true``, then watchdog-based self-fencing will be performed via SBD when fencing is required. If this is set to a positive value, lost nodes are assumed to achieve self-fencing within this much time. This does not require a fencing resource to be explicitly configured, though a fence_watchdog resource can be configured, to limit use to specific nodes. If this is set to 0 (the default), the cluster will never assume watchdog-based self-fencing. If this is set to a negative value, the cluster will use twice the local value of the ``SBD_WATCHDOG_TIMEOUT`` environment variable if that is positive, or otherwise treat this as 0. **Warning:** When used, this timeout must be larger than ``SBD_WATCHDOG_TIMEOUT`` on all nodes that use watchdog-based SBD, and Pacemaker will refuse to start on any of those nodes where this is not true for the local value or SBD is not active. When this is set to a negative value, ``SBD_WATCHDOG_TIMEOUT`` must be set to the same value on all nodes that use SBD, otherwise data corruption or loss could occur. * - .. _concurrent-fencing: .. index:: pair: cluster option; concurrent-fencing concurrent-fencing - :ref:`boolean ` - false - Whether the cluster is allowed to initiate multiple fence actions concurrently. Fence actions initiated externally, such as via the ``stonith_admin`` tool or an application such as DLM, or by the fencer itself such as recurring device monitors and ``status`` and ``list`` commands, are not limited by this option. * - .. _fence_reaction: .. index:: pair: cluster option; fence-reaction fence-reaction - :ref:`enumeration ` - stop - How should a cluster node react if notified of its own fencing? A cluster node may receive notification of a "succeeded" fencing that targeted it if fencing is misconfigured, or if fabric fencing is in use that doesn't cut cluster communication. Allowed values are ``stop`` to attempt to immediately stop Pacemaker and stay stopped, or ``panic`` to attempt to immediately reboot the local node, falling back to stop on failure. The default is likely to be changed to ``panic`` in a future release. *(since 2.0.3)* * - .. _priority_fencing_delay: .. index:: pair: cluster option; priority-fencing-delay priority-fencing-delay - :ref:`duration ` - 0 - Apply this delay to any fencing targeting the lost nodes with the highest total resource priority in case we don't have the majority of the nodes in our cluster partition, so that the more significant nodes potentially win any fencing match (especially meaningful in a split-brain of a 2-node cluster). A promoted resource instance takes the resource's priority plus 1 if the resource's priority is not 0. Any static or random delays introduced by ``pcmk_delay_base`` and ``pcmk_delay_max`` configured for the corresponding fencing resources will be added to this delay. This delay should be significantly greater than (safely twice) the maximum delay from those parameters. *(since 2.0.4)* * - .. _node_pending_timeout: .. index:: pair: cluster option; node-pending-timeout node-pending-timeout - :ref:`duration ` - 0 - Fence nodes that do not join the controller process group within this much time after joining the cluster, to allow the cluster to continue managing resources. A value of 0 means never fence pending nodes. Setting the value to 2h means fence nodes after 2 hours. *(since 2.1.7)* * - .. _cluster_delay: .. index:: pair: cluster option; cluster-delay cluster-delay - :ref:`duration ` - 60s - If the DC requires an action to be executed on another node, it will consider the action failed if it does not get a response from the other node within this time (beyond the action's own timeout). The ideal value will depend on the speed and load of your network and cluster nodes. * - .. _dc_deadtime: .. index:: pair: cluster option; dc-deadtime dc-deadtime - :ref:`duration ` - 20s - How long to wait for a response from other nodes when electing a DC. The ideal value will depend on the speed and load of your network and cluster nodes. * - .. _cluster_ipc_limit: .. index:: pair: cluster option; cluster-ipc-limit cluster-ipc-limit - :ref:`nonnegative integer ` - 500 - The maximum IPC message backlog before one cluster daemon will disconnect another. This is of use in large clusters, for which a good value is the number of resources in the cluster multiplied by the number of nodes. The default of 500 is also the minimum. Raise this if you see "Evicting client" log messages for cluster daemon process IDs. * - .. _pe_error_series_max: .. index:: pair: cluster option; pe-error-series-max pe-error-series-max - :ref:`integer ` - -1 - The number of scheduler inputs resulting in errors to save. These inputs can be helpful during troubleshooting and when reporting issues. A negative value means save all inputs, and 0 means save none. * - .. _pe_warn_series_max: .. index:: pair: cluster option; pe-warn-series-max pe-warn-series-max - :ref:`integer ` - 5000 - The number of scheduler inputs resulting in warnings to save. These inputs can be helpful during troubleshooting and when reporting issues. A negative value means save all inputs, and 0 means save none. * - .. _pe_input_series_max: .. index:: pair: cluster option; pe-input-series-max pe-input-series-max - :ref:`integer ` - 4000 - The number of "normal" scheduler inputs to save. These inputs can be helpful during troubleshooting and when reporting issues. A negative value means save all inputs, and 0 means save none. * - .. _enable_acl: .. index:: pair: cluster option; enable-acl enable-acl - :ref:`boolean ` - false - Whether :ref:`access control lists ` should be used to authorize CIB modifications * - .. _placement_strategy: .. index:: pair: cluster option; placement-strategy placement-strategy - :ref:`enumeration ` - default - How the cluster should assign resources to nodes (see :ref:`utilization`). Allowed values are ``default``, ``utilization``, ``balanced``, and ``minimal``. * - .. _node_health_strategy: .. index:: pair: cluster option; node-health-strategy node-health-strategy - :ref:`enumeration ` - none - How the cluster should react to :ref:`node health ` attributes. Allowed values are ``none``, ``migrate-on-red``, ``only-green``, ``progressive``, and ``custom``. * - .. _node_health_base: .. index:: pair: cluster option; node-health-base node-health-base - :ref:`score ` - 0 - The base health score assigned to a node. Only used when ``node-health-strategy`` is ``progressive``. * - .. _node_health_green: .. index:: pair: cluster option; node-health-green node-health-green - :ref:`score ` - 0 - The score to use for a node health attribute whose value is ``green``. Only used when ``node-health-strategy`` is ``progressive`` or ``custom``. * - .. _node_health_yellow: .. index:: pair: cluster option; node-health-yellow node-health-yellow - :ref:`score ` - 0 - The score to use for a node health attribute whose value is ``yellow``. Only used when ``node-health-strategy`` is ``progressive`` or ``custom``. * - .. _node_health_red: .. index:: pair: cluster option; node-health-red node-health-red - :ref:`score ` - -INFINITY - The score to use for a node health attribute whose value is ``red``. Only used when ``node-health-strategy`` is ``progressive`` or ``custom``. * - .. _cluster_recheck_interval: .. index:: pair: cluster option; cluster-recheck-interval cluster-recheck-interval - :ref:`duration ` - 15min - Pacemaker is primarily event-driven, and looks ahead to know when to recheck the cluster for failure-timeout settings and most time-based rules *(since 2.0.3)*. However, it will also recheck the cluster after this amount of inactivity. This has three main effects: * :ref:`Rules ` using ``date_spec`` are guaranteed to be checked only this often. * If :ref:`fencing ` fails enough to reach :ref:`stonith-max-attempts `, attempts will begin again after at most this time. * It serves as a fail-safe in case of certain scheduler bugs. If the scheduler incorrectly determines only some of the actions needed to react to a particular event, it will often correctly determine the rest after at most this time. A value of 0 disables this polling. * - .. _shutdown_lock: .. index:: pair: cluster option; shutdown-lock shutdown-lock - :ref:`boolean ` - false - The default of false allows active resources to be recovered elsewhere when their node is cleanly shut down, which is what the vast majority of users will want. However, some users prefer to make resources highly available only for failures, with no recovery for clean shutdowns. If this option is true, resources active on a node when it is cleanly shut down are kept "locked" to that node (not allowed to run elsewhere) until they start again on that node after it rejoins (or for at most ``shutdown-lock-limit``, if set). Stonith resources and Pacemaker Remote connections are never locked. Clone and bundle instances and the promoted role of promotable clones are currently never locked, though support could be added in a future release. Locks may be manually cleared using the ``--refresh`` option of ``crm_resource`` (both the resource and node must be specified; this works with remote nodes if their connection resource's ``target-role`` is set to ``Stopped``, but not if Pacemaker Remote is stopped on the remote node without disabling the connection resource). *(since 2.0.4)* * - .. _shutdown_lock_limit: .. index:: pair: cluster option; shutdown-lock-limit shutdown-lock-limit - :ref:`duration ` - 0 - If ``shutdown-lock`` is true, and this is set to a nonzero time duration, locked resources will be allowed to start after this much time has passed since the node shutdown was initiated, even if the node has not rejoined. (This works with remote nodes only if their connection resource's ``target-role`` is set to ``Stopped``.) *(since 2.0.4)* * - .. _startup_fencing: .. index:: pair: cluster option; startup-fencing startup-fencing - :ref:`boolean ` - true - *Advanced Use Only:* Whether the cluster should fence unseen nodes at start-up. Setting this to false is unsafe, because the unseen nodes could be active and running resources but unreachable. ``dc-deadtime`` acts as a grace period before this fencing, since a DC must be elected to schedule fencing. * - .. _election_timeout: .. index:: pair: cluster option; election-timeout election-timeout - :ref:`duration ` - 2min - *Advanced Use Only:* If a winner is not declared within this much time of starting an election, the node that initiated the election will declare itself the winner. * - .. _shutdown_escalation: .. index:: pair: cluster option; shutdown-escalation shutdown-escalation - :ref:`duration ` - 20min - *Advanced Use Only:* The controller will exit immediately if a shutdown does not complete within this much time. * - .. _join_integration_timeout: .. index:: pair: cluster option; join-integration-timeout join-integration-timeout - :ref:`duration ` - 3min - *Advanced Use Only:* If you need to adjust this value, it probably indicates the presence of a bug. * - .. _join_finalization_timeout: .. index:: pair: cluster option; join-finalization-timeout join-finalization-timeout - :ref:`duration ` - 30min - *Advanced Use Only:* If you need to adjust this value, it probably indicates the presence of a bug. * - .. _transition_delay: .. index:: pair: cluster option; transition-delay transition-delay - :ref:`duration ` - 0s - *Advanced Use Only:* Delay cluster recovery for the configured interval to allow for additional or related events to occur. This can be useful if your configuration is sensitive to the order in which ping updates arrive. Enabling this option will slow down cluster recovery under all conditions.