Removing Lock Disk

[Darren Murray]

Hi ,

I have a 3 node cluster which used to be a 2 node cluster. I need to use the 2 disks that I had as the lock disk now as a normal volume group.

Do I have to shutdown the cluster?

If I do, is it a matter of doing a cmgetconf and taking out the FIRST_CLUSTER_LOCK_VG and FIRST_CLUSTER_LOCK_PV references. Then re-applying the new ascii file? Then doing a vgexport of the lock disk group?.

I will be adding a lock disk later but time is against me and I need the disks now.

Many thanks
Darren

[Carsten Krege]

When you want to remove the cluster lock disk from your configuration, you need to halt the cluster, remove the statements FIRST_CLUSTER_LOCK_VG and FIRST_CLUSTER_LOCK_PV from the cluster.ascii file for all nodes configured and reapply the config using cmapplyconf.

If the third node can connect to the cluster lock disk, you can also continue to use the cluster lock disk in a three node cluster. In this case you need to make the VG accessible for the new node (vgimport), add the node in the cluster ascii file, specifying FIRST_CLUSTER_LOCK_PV and reapply the configuration.

Cluster lock disks are allowed in configurations with up to 4 nodes.

Carsten

[Christopher McCray_1]

You can use a disk on a normal volume group as a clusteter lock vg and pv; All this means is that a cluster lock mark is placed in the BDRA of the disk in question. However, if you wanted to change this, you will have to bring down the cluster. Then:

# cmgetconf -c temp.ascii
# cmquerycl -n -n -n -C cluster.ascii
# vi cluster.ascii ( to incorporate any previous settings from the old cofiguration)
# cmcheckconf -C cluster.ascii
# cmapplyconf -C cluster.ascii
# cmruncl

Hope this helps
Chris

[Christopher McCray_1]

You can also just edit the cluster config file, manually enter the cluster lock vg and pv, check then apply the config file. In either the case above or tis one, the cluster must be stopped/started. I also restate that the cluster lock disk can be used concurrently with data, as long as all nodes in a cluster can see it. Good luck.

Chris