Remove one node from 2 node cluster.

[kpatel786]

Hi,

On one the servers I have 2 two clusters.
I want to remove one node from the cluster and let one node has it is.

As far a I know need to perform the below steps:

Removing the package:
1) Halt the package
2) remove the package from the cluster using cmdelete conf
3) delete the package subdirectory on each node in the cluster
4) free up any resources, remove mount points etc from the nodes that this package may have used.

Removing the node:
1) Halt the node using cmhaltnode
2) remove the node from any package configuration file that may have this node listed
3) reapply each package that you change in step 2
4) edit the cluster ascii file, deleting the referenced node
5) apply the change with cmapplyconf

Kindly confirm if there is anything else besides the above steps.
Also the single node remaining will it continue to function normaly without any issue.
Will there be any issues when the server is rebooted.

Thanking you inadvance

[Jupinder Bedi · Accepted solution]

Backup the current configuration file.
Halt the node to be removed

cmhaltnode -n nodename

Delete all references to the soon to be removed node in all package config files
Obtain a current cluster configuration file

cmgetconf configuration file

Edit the configuraton file and comment out
all references to the node to be removed.

cmcheckconf -C configuration file}
cmapplyconf -C configuration file

[kpatel786]

Thanks for the reply.

My question will this effect the single node running on the system after the removal.
I mean it will become a single node cluster so when the system is rebooted will it look for cluster formation
Also, what will happen when the system goes in hung status what will happen to existing node will it be able to failover to other server?

[sahir_1]

By doing following you can remove the node 2 from cluster

cmhaltnode -n nodename
cmgetconf configfile

comment all line referred to the node to be removed.
cmcheckconf -C configfile
cmapplyconf -C configfile

Single node can run with the same cluster without any problem even after reboot
and if one network card fail it can move to standby network card.

[Stephen Doud]

To remove a node from a cluster, do the following:
1) halt all packages on the departing node
2) halt the cluster daemons on the departing node
3) edit the package configuration file(s), removing the NODE_NAME reference for the departing node
4) edit the cluster configuration file, removing the section referring to the departing node. Optionally, remove the cluster arbitration references (quorum server or cluster lock VG), since a 1-node cluster does not need them).
5) perform cmapplyconf on both the package and cluster configuration files simultaneously.

If you no longer need the package, use the following command to remove it from cluster references:
# cmdeleteconf -p
After doing so, remove the package directory from each node.

At this point, the remaining node should be able to form a one-node cluster at boot time.

You asked about the ramification of a system hang. Serviceguard employs a kernel-based timer that, when not reset by Serviceguard (due to a hang) eventually times out and forces a system core dump/reboot.

[kpatel786]

Thank you all for your time and help.