VCS : Configure GAB manually



VCS uses the Group Membership Services/Atomic Broadcast (GAB) protocol for cluster membership and reliable cluster communications. GAB has two major functions.

It handles the following tasks:

  • Cluster membership
  • Cluster communications




To configure GAB

  1. Set up an /etc/gabtab configuration file on each node in the cluster using vi or another editor. The following example shows an /etc/gabtab file:
        /sbin/gabconfig -c -nN

    Where the -c option configures the driver for use. The -nN option specifies that the cluster is not formed until at least N systems are ready to form the cluster. Symantec recommends that you set N to be the total number of systems in the cluster.

    Warning: Symantec does not recommend the use of the -c -x option for /sbin/gabconfig. Using -c -x can lead to a split-brain condition.

  2. Edit the following file on each node in the cluster to change the values of the GAB_START and the GAB_STOP environment variables to 1:/etc/default/gab


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5 Responses

  1. krishna says:

    Hi.This is krishna..I read somewhere that we can give the command gabconfig -c -x to solve if there is GAB problem or HAD problem in the output of gabconfig -a. But here Symantec does not recommend the use of the -c -x option for /sbin/gabconfig. Using -c -x can lead to a split-brain condition. Finally my question is whether we can use this command or not if we have a problem with gabconfig output..ill wait for your reply..

  1. September 18, 2015

    […] Read – VCS for Beginners – Configure GAB manually […]

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