Forum Discussion

linuly's avatar
linuly
Level 4
6 years ago

vcs node

hi i like to clarify. when a node join to vcs then in its memory all the information from the other nodes are filled.thus this node sees if there he should bring up the resource group that normally...
  • frankgfan's avatar
    frankgfan
    6 years ago

    Hello,

    In CVM configuration, any vx* commands which will lead to a vxvm configuration change (commjands like vxassist, vxmake, vxsd, vxplex etc) need to be executed on the CVM master (with new releases from 6.2, the command can be issued on any nodes as now there is a GAB port y which can ship commands to the cvm master for execution).

    VCS commands like hares, hagrp, haclus etc do not change VxVM metadata so can be executed on any nodes in the cluster, so long as the node is in online running state in the cluster.

    Frank

frankgfan's avatar
frankgfan
Moderator

Hello,

 

when a node starts and if there is another node in running state, the node will take a snapshot of cvs configuration from the running node via llt network.  you can see this info from engine_A.log.  if there is not any node in running state, the node will read on disk vcs configuation (main,cf) and buid up the cluster.

 

if a node is shutdown, hastop command will be executed as part of system shutdown,  since a system shutdown is considered as a system admin action, not a true failure., vcs service groups may not be switched over.

 

here are some hastop command options and their meanings:

    The -local option stops the VCS server on the system on which the command is issued. When the VCS server stops a system, the system’s service groups are also stopped.

   The -force option stops the VCS server, but allows the service groups to continue running.

   The -evacuate option migrates all groups to other systems, if possible.

   The -noautodisable option ensures that service groups that can run on the node for which hastop is invoked are not autodisabled while VCS is stopped. The -noautodisable option can also be used with -evacuate option, but not with -force option.

please also read this technote https://support.symantec.com/en_US/article.TECH11477.htm to know some vcs behavior in a system restart.

Frank

 

linuly's avatar
linuly
Level 4
6 years ago

Hi,

In vcs cluster an designated coordinator is elected.When the cluster is running every hagrp,hares including resource switch  so on command will talk to DC.right?

tnx

 

  • frankgfan's avatar
    frankgfan
    Moderator
    6 years ago

    Hello,

    there are two types VCS configurations:  failover and CVM (cluster volume manager, also known as parallel configuration).  In CVM configuration there is one node elected as a CVM master.

    In failover configuration (a service group is onlined on one node at any given time) there is no master node.

    Can you please elaberate the followings?

    1. an designated coordinator 

    2. DC

    is your cluster running on Windows platform or Unix?

    Frank

    • linuly's avatar
      linuly
      Level 4
      6 years ago

      hi,

      it was my mistake.Unix i run.

      In vcs case if i add or modify a resource from any node with hares then the main.cf of every node is updated and data in memory the same.right?

      hares command from the node i given is copied in every node and in every node hares talk to had and this write to main.cf.right?

      tnx

       

      • frankgfan's avatar
        frankgfan
        Moderator
        6 years ago

        Hello,

        In CVM configuration, any vx* commands which will lead to a vxvm configuration change (commjands like vxassist, vxmake, vxsd, vxplex etc) need to be executed on the CVM master (with new releases from 6.2, the command can be issued on any nodes as now there is a GAB port y which can ship commands to the cvm master for execution).

        VCS commands like hares, hagrp, haclus etc do not change VxVM metadata so can be executed on any nodes in the cluster, so long as the node is in online running state in the cluster.

        Frank