Deleting node from the cluster ??

[Avarsang Shankar]

How do I delete a node, which has no pkgs running, from the cluster ?

[Sundar_7 · Accepted solution]

Create a new cluster configuration using cmquerycl command

Say if you have a three node cluster node1,node2 and node3. To remove node3 from the cluster

# cmquerycl -v -C cluster.conf -n node1 -n node2

Stop the MC-SG on node3

# cmhaltnode -f node3

The cluster needs to be halted before cmapplyconf command if you are running MC-SG version earlier than A.10.10 .

# cmcheckconf -C cluster.conf

# cmapplyconf -C cluster.conf

[John Kittel]

permanently remove a node from a cluster, for example changing a 3 node cluster permanently into a 2 node cluster?

or, temporarily, say for just this morning, temporarily removing a node from a cluster, and then adding it back in a little while later?

[Sundar_7]

Also if you did nt have a cluster lock disk defined in the cluster configuration file, you should define one if the number of nodes that are goign to form the cluster equals to 2.

Even with the latest SG versions, cluster needs to be halted to define/change the cluster lock configuration and you might like to export and remove all the shared VGs from the node's /etc/lvmtab file.

[Avarsang Shankar]

I have a 5 node cluster out of which I need to remove one of them permanently. The MC-SG version is 11.14. No clust lock vg defined

So can I cmapplyconf while other nodes & pkgs are up and running ?

[Sundar_7]

Yes, I believe you could just cmquerycl, cmhaltnode, cmcheckconf and cmapplyconf.

Just make sure you remove the reference for the node from all the package configurations too, if any.

cd /etc/cmcluster/
cmgetconf -p
edit the package configuration file to remove the node you are removing from the adoptive_node list if any.

on a nutshell this is howI would do it

# cd /etc/cmcluster
# cmquerycl -v -C cluster.conf -n node1 -n node2 -n node3 -n noe4
# cd
# cmgetconf -p
# vi
..
..
NODE_NAME node1
NODE_NAMe node5
..
to
NODE_NAME node1
#

remove the NODE_NAME reference for node5 from all the package configuration files that refer node5

# cmhaltnode -f node5

# cmcheckconf -C cluster.conf -p pkg1/pkg1.conf -p pkg2/pkg2.conf ....

# cmapplyconf -C cluster.conf -p pkg1/pkg1.conf -p pkg2/pkg2.conf ....

on node5

# vi /etc/rc.config.d/cmcluster
AUTOSTART_CMCLD=0
#

Node5

# vi /etc/lvmrc
AUTO_VG_ACTIVATE=1
#

Node5

# vgexport /dev/vg_shared1

# vgexport /dev/vg_shared2

have a reboot of node5

[Geoff Wild]

Make sure you:

cmhaltnode serverbyby

first - before you re-do the cluster with a cmquerycl/cmapplyconf (or , better yet, just vi your conf file, rmove the node, then cmapplyconf).

Rgds...Geoff

[Stephen Doud]

This document: UXSGKBAN00000021
TITLE:How to decommission a Serviceguard Cluster, Package, Node or VG

... will step you through the process.

Since the node is not an adopter of any packages, the method is as follows:

1) locate the cluster configuration file
(use 'cmgetconf ' if you cannot locate it)

2) remove the section describing the node that is leaving the cluster

3) cmhaltnode that node and perform a
# cmapplyconf -k -f -C
The node will be removed from the cluster.

4) insure /etc/rc.config.d/cmcluster AUTOSTART_CMCLD=0 on that node.

5) vgexport shared vg's

6) if /etc/lvmrc AUTO_VG_ACTIVATE=0, set it to 1

7) update the /etc/fstab mount table if any shared VG's become private to the departing node

-StephenD.