Adding a node to an active VCS cluster

Whilst on a customer site in Scotland earlier this month, I was asked by the end-user to add a new node to an existing VCS; Primarily they were going through a hardware upgrade so they wanted the resilience of a third node.

In this article we will add a third node (vcsdevnod03) to the existing 2 node cluster.

Installing VCS software

Install the VCS cluster software on the new node (vcsdevnod03) from the software media.

NOTE: When asked to configure it, select 'No'.

Configuring the new node

1. On the third node, change directory to the software media, and start the VCS installation/configuration process with the -addnode option. For example:

   # cd /cdrom/VRTSvcs
   # ./installsf -addnode

2. When prompted, enter the name of an existing cluster node:

   Enter a node of SF cluster to which you want to add a node: vcsdevnod01

3. At this point the install process will probe the existing node

   Checking communication on vcsdevnod01 .................. Done
   Checking release compatibility on vcsdevnod01 .......... Done

4. The install process will provide the clustomer name and the names of the oher members of the cluster, if this is correct simply reply 'y' when prompted:

   Following cluster information detected: Cluster Name: vcsdev
   Cluster ID: 3
   Systems: vcsdevnod01 vcsdevnod02
   Is this information correct? [y,n,q] (y)? y

5. The install process will now perform the necessary communication checks and run states for all cluster nodes:

   Checking communication on vcsdevnod03 ................. Done
   Checking VCS running state on vcsdevnod01 ............. Done
   Checking VCS running state on vcsdevnod02 ............. Done
   Checking VCS running state on vcsdevnod03 ............. Done

6. You now be prompted to enter the name of the new node into the cluster:

   Enter the system names separated by spaces to add to the cluster:? vcsdevnod03

7. Once additional checks are completed, you will be prompted to confirm that this new node is to be a member of the VCS cluster:

   Checking communication on vcsdevnod03.................. Done
   Checking release compatibility on vcsdevnod03.......... Done
   Do you want to add the system(s) vcsdevnod03 to the cluster vcsdev? [y,n,q] (y)? y

8. The install process will now discover the network interfaces available for usage, enter the appropriate entries for your NICs:

   Discovering NICs on vcsdevnod03 ... Discovered nxge0 nxge1 nxge2 nxge3
   To use aggregated interfaces for private heartbeat, enter the name of an aggregated interface.
   To use a NIC for private heartbeat, enter a NIC which is not part of an aggregated interface.
   Enter the NIC for the first private heartbeat link on vcsdevnod03: [b,q,?]? nxge2
   Would you like to configure a second private heartbeat link? [y,n,q,b,?] (y)? y
   Enter the NIC for the second private heartbeat link on vcsdevnod03: [b,q,?]? nxge3
   Would you like to configure a third private heartbeat link? [y,n,q,b,?] (n)? n
   Do you want to configure an additional low priority heartbeat link? [y,n,q,b,?] (n)? n
   Checking Media Speed for nxge2 on vcsdevnod03 ......... 1000 
   Checking Media Speed for nxge3 on vcsdevnod03 ......... 1000

9. Confirm the NICs to be used:

   Private Heartbeat NICs for vcsdevnod03:
   link1=nxge2
   link2=nxge3
   Is this information correct? [y,n,q] (y)? y

10. In the case where you have configured a virtual cluster IP

    Cluster Virtual IP is configured on the cluster vcsdev
    A public NIC device is required by following services on each of the newly added nodes:
    Cluster Virtual IP
    Active NIC devices discovered on vcsdevnod03: nxge0 nxge1
    Enter the NIC for the VCS to use on vcsdevnod03: (nxge0)
    nxge0

Verify configuration

Confirm the configuration by running the following commands on vcsdevnod03:

# lltstat -nvv
# cat /etc/llttab
# cat /etc/llthosts
# gabconfig -a
# cat /etc/gabtab
# vxfenadm -d
# cat /etc/vxfenmode
# cat /etc/VRTSvcs/conf/config/main.cf

NOTE: ClusterServices Sg should have vcsdevnod03)

Final process

If all of the above settings are right then dump the VCS configuration in memory to main.cf

# haconf -makerw