RHEL 6 Cluster Admin - 6.3. Managing High-Availability Services

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6.3. Managing High-Availability Services

You can manage high-availability services using the Cluster Status Utility, clustat, and the Cluster User Service Administration Utility, clusvcadm. clustat displays the status of a cluster and clusvcadm provides the means to manage high-availability services.

This section provides basic information about managing HA services using clustat and clusvcadm It consists of the following subsections:

6.3.1. Displaying HA Service Status with `clustat`

clustat displays cluster-wide status. It shows membership information, quorum view, the state of all high-availability services, and indicates which node the clustat command is being run at (Local). Table 6.1, “Services Status” describes the states that services can be in and are displayed when running clustat. Example 6.3, “clustat Display” shows an example of a clustat display. For more detailed information about running the clustat command refer to the clustat man page.

Table 6.1. Services Status

Services Status	Description
Started	The service resources are configured and available on the cluster system that owns the service.
Recovering	The service is pending start on another node.
Disabled	The service has been disabled, and does not have an assigned owner. A disabled service is never restarted automatically by the cluster.
Stopped	In the stopped state, the service will be evaluated for starting after the next service or node transition. This is a temporary state. You may disable or enable the service from this state.
Failed	The service is presumed dead. A service is placed into this state whenever a resource's stop operation fails. After a service is placed into this state, you must verify that there are no resources allocated (mounted file systems, for example) prior to issuing a `disable` request. The only operation that can take place when a service has entered this state is `disable`.
Uninitialized	This state can appear in certain cases during startup and running `clustat -f`.

Example 6.3. `clustat` Display

[root@example-01 ~]#clustat
Cluster Status for mycluster @ Wed Nov 17 05:40:15 2010
Member Status: Quorate

 Member Name                             ID   Status
 ------ ----                             ---- ------
 node-03.example.com                         3 Online, rgmanager
 node-02.example.com                         2 Online, rgmanager
 node-01.example.com                         1 Online, Local, rgmanager

 Service Name                   Owner (Last)                   State         
 ------- ----                   ----- ------                   -----           
 service:example_apache         node-01.example.com            started       
 service:example_apache2        (none)                         disabled

6.3. Managing High-Availability Services

6.3.1. Displaying HA Service Status with clustat

Table 6.1. Services Status

Example 6.3. clustat Display

6.3.1. Displaying HA Service Status with `clustat`

Example 6.3. `clustat` Display