Administration guide > Configure the deployment environment > Configuring catalog and container servers



Configure quorum

The quorum mechanism is disabled by default. Use one of the following methods to enable quorum. All the catalog servers must be given the same quorum setting.

Quorum is the minimum number of catalog servers that are necessary to conduct placement operations for the data grid. The minimum number is the full set of catalog servers unless you override the quorum value.


Procedure

  1. Enable quorum on the catalog servers.
    In WebSphere Application Server, configure quorum with the server properties file. In a stand-alone environment you can either use the properties method or enable quorum when you start the server:

    • Set the enableQuorum=true property in the server properties file.

      Use this configuration in a WebSphere Application Server or stand-alone environment.

      Figure 1. objectGridServer.properties file

      catalogClusterEndPoints=cat0:cat0.domain.com:6600:6601,
      cat1:cat1.domain.com:6600:6601
      catalogServiceEndPoints= cat0.domain.com:2809, cat1.domain.com:2809
      enableQuorum=true
      

      For more information about configuring the properties file, see Server properties file

    • Pass the -quorum enabled flag on the startOgServer command.

      Use this configuration method when you start stand-alone servers only.

      # bin/startOgServer cat0 –serverProps objectGridServer.properties -quorum true
      

      For more information about the startOgServer command, see startOgServer script.

  2. Start container servers in the same zone.

    Start container servers with the startOgServer command. When you are running a data grid across data centers, the servers must use the zone information to identify the data center in which they reside. Setting the zone on the container servers allows WebSphere eXtreme Scale to monitor health of the container servers that are scoped to the data center, minimizing cross-data-center traffic.

    # bin/startOgServer gridA0 –serverProps objectGridServer.properties –objectgridfile 
    xml/objectgrid.xml –deploymentpolicyfile xml/deploymentpolicy.xml
    

    The following snippet of the objectGridServer.properties file defines the zone to which the container server belongs: :

    catalogServiceEndPoints= cat0.domain.com:2809, cat1.domain.com:2809
    zoneName=ZoneA
    


Results

The catalog service has quorum when the full set of catalog servers is running. You override the quorum value if a data center failure occurs. Quorum loss due to a catalog service JVM failure or a network brownout should recover automatically after the catalog service JVM is restarted or the network brownout clears.


Parent topic:

Configure catalog and container servers


Related concepts

Best practice: Clustering the catalog service

Catalog server quorums

Catalog service


Related tasks

Configure WebSphere eXtreme Scale with WAS

Configure multi-master replication topologies

Ovveride catalog service quorum

Monitor with the xsAdmin sample utility

Related reference

Server properties file