-[[chapter-ha-manager]]
+[[chapter_ha_manager]]
ifdef::manvolnum[]
-PVE({manvolnum})
-================
-include::attributes.txt[]
+ha-manager(1)
+=============
+:pve-toplevel:
NAME
----
DESCRIPTION
-----------
endif::manvolnum[]
-
ifndef::manvolnum[]
High Availability
=================
-include::attributes.txt[]
+:pve-toplevel:
endif::manvolnum[]
-
Our modern society depends heavily on information provided by
computers over the network. Mobile devices amplified that dependency,
because people can access the network any time from anywhere. If you
software:
* Use reliable ``server'' components
-
++
NOTE: Computer components with same functionality can have varying
reliability numbers, depending on the component quality. Most vendors
sell components with higher reliability as ``server'' components -
times of about 2 minutes, so you can get no more than 99.999%
availability.
+
Requirements
------------
+You must meet the following requirements before you start with HA:
+
* at least three cluster nodes (to get reliable quorum)
* shared storage for VMs and containers
* hardware redundancy (everywhere)
+* use reliable “server” components
+
* hardware watchdog - if not available we fall back to the
linux kernel software watchdog (`softdog`)
* optional hardware fencing devices
+[[ha_manager_resources]]
Resources
---------
`pve-ha-lrm`::
-The local resource manager (LRM), it controls the services running on
-the local node.
-It reads the requested states for its services from the current manager
-status file and executes the respective commands.
+The local resource manager (LRM), which controls the services running on
+the local node. It reads the requested states for its services from
+the current manager status file and executes the respective commands.
`pve-ha-crm`::
-The cluster resource manager (CRM), it controls the cluster wide
-actions of the services, processes the LRM results and includes the state
-machine which controls the state of each service.
+The cluster resource manager (CRM), which makes the cluster wide
+decisions. It sends commands to the LRM, processes the results,
+and moves resources to other nodes if something fails. The CRM also
+handles node fencing.
+
.Locks in the LRM & CRM
[NOTE]
quorum the node cannot reset the watchdog. This will trigger a reboot
after the watchdog then times out, this happens after 60 seconds.
+
Configuration
-------------
-The HA stack is well integrated in the Proxmox VE API2. So, for
-example, HA can be configured via `ha-manager` or the PVE web
-interface, which both provide an easy to use tool.
+The HA stack is well integrated into the {pve} API. So, for example,
+HA can be configured via the `ha-manager` command line interface, or
+the {pve} web interface - both interfaces provide an easy way to
+manage HA. Automation tools can use the API directly.
+
+All HA configuration files are within `/etc/pve/ha/`, so they get
+automatically distributed to the cluster nodes, and all nodes share
+the same HA configuration.
+
+
+Resources
+~~~~~~~~~
+
+The resource configuration file `/etc/pve/ha/resources.cfg` stores
+the list of resources managed by `ha-manager`. A resource configuration
+inside that list look like this:
+
+----
+<type>:<name>
+ <property> <value>
+ ...
+----
+
+It starts with a resource type followed by a resource specific name,
+separated with colon. Together this forms the HA resource ID, which is
+used by all `ha-manager` commands to uniquely identify a resource
+(example: `vm:100` or `ct:101`). The next lines contain additional
+properties:
+
+include::ha-resources-opts.adoc[]
+
+
+Groups
+~~~~~~
+
+The HA group configuration file `/etc/pve/ha/groups.cfg` is used to
+define groups of cluster nodes. A resource can be restricted to run
+only on the members of such group. A group configuration look like
+this:
+
+----
+group: <group>
+ nodes <node_list>
+ <property> <value>
+ ...
+----
+
+include::ha-groups-opts.adoc[]
-The resource configuration file can be located at
-`/etc/pve/ha/resources.cfg` and the group configuration file at
-`/etc/pve/ha/groups.cfg`. Use the provided tools to make changes,
-there shouldn't be any need to edit them manually.
Node Power Status
-----------------
a watchdog reset.
+[[ha_manager_fencing]]
Fencing
-------
unresponsive node and as a result a chain reaction of node failures in the
cluster.
+[[ha_manager_groups]]
Groups
------
* *after* you fixed all errors you may enable the service again
+[[ha_manager_service_operations]]
Service Operations
------------------