Red Hat Cluster Suite: Configuring and Managing a Cluster
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4.2. Displaying Cluster and Service Status

Monitoring cluster and application service status can help identify and resolve problems in the cluster environment. The following tools assist in displaying cluster status information:

The Cluster Status Tool
The clustat utility

	Important
	Members that are not running the cluster software cannot determine or report the status of other members of the cluster.

Cluster and service status includes the following information:

Cluster member system status
Service status and which cluster system is running the service or owns the service

The following tables describe how to analyze the status information shown by the Cluster Status Tool and the clustat utility.

Member Status Description

Member

The node is part of the cluster.

Note: A node can be a member of a cluster; however, the node may be inactive and incapable of running services. For example, if rgmanager is not running on the node, but all other cluster software components are running in the node, the node appears as a Member in the Cluster Status Tool. However, without rgmanager running, the node does not appear in the clustat display.

Dead The member system is unable to participate as a cluster member. The most basic cluster software is not running on the node.

Table 4-1. Member Status for the Cluster Status Tool

Member Status Description

Online The node is communicating with other nodes in the cluster.

Inactive

The node is unable to communicate with the other nodes in the cluster. If the node is inactive, clustat does not display the node. If rgmanager is not running in a node, the node is inactive.

Note: Although a node is inactive, it may still appear as a Member in the Cluster Status Tool. However, if the node is inactive, it is incapable of running services.

Table 4-2. Member Status for clustat

Service Status	Description
Started	The service resources are configured and available on the cluster system that owns the service.
Pending	The service has failed on a member and is pending start on another member.
Disabled	The service has been disabled, and does not have an assigned owner. A disabled service is never restarted automatically by the cluster.
Stopped	The service is not running; it is waiting for a member capable of starting the service. A service remains in the stopped state if autostart is disabled.
Failed	The service has failed to start on the cluster and cannot successfully stop the service. A failed service is never restarted automatically by the cluster.

Table 4-3. Service Status

The Cluster Status Tool displays the current cluster status in the Services area and automatically updates the status every 10 seconds. Additionally, you can display a snapshot of the current cluster status from a shell prompt by invoking the clustat utility. Example 4-1 shows the output of the clustat utility.

# clustat
Member Status: Quorate, Group Member
 
  Member Name                              State      ID
  ------ ----                              -----      --
  tng3-2                                   Online     0x0000000000000002
  tng3-1                                   Online     0x0000000000000001
 
  Service Name         Owner (Last)                   State
  -------- -----       ----- ------                   -----
  webserver            (tng3-1                      ) failed
  email                tng3-2                         started

Example 4-1. Output of clustat

To monitor the cluster and display status at specific time intervals from a shell prompt, invoke clustat with the -i time option, where time specifies the number of seconds between status snapshots. The following example causes the clustat utility to display cluster status every 10 seconds:

#clustat -i 10

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