You can enable or disable the preferred fencing feature for your I/O fencing configuration.
You can enable preferred fencing to use system-based race policy or group-based race policy. If you disable preferred fencing, the I/O fencing configuration uses the default count-based race policy.
To enable preferred fencing for the I/O fencing configuration
# vxfenadm -d
# haclus -value UseFence
To enable system-based race policy, perform the following steps:
Make the VCS configuration writable.
# haconf -makerw
Set the value of the cluster-level attribute PreferredFencingPolicy as System.
# haclus -modify PreferredFencingPolicy System
Set the value of the system-level attribute FencingWeight for each node in the cluster.
For example, in a two-node cluster, where you want to assign galaxy five times more weight compared to nebula, run the following commands:
# hasys -modify galaxy FencingWeight 50 # hasys -modify nebula FencingWeight 10
Save the VCS configuration.
# haconf -dump -makero
To enable group-based race policy, perform the following steps:
Make the VCS configuration writable.
# haconf -makerw
Set the value of the cluster-level attribute PreferredFencingPolicy as Group.
# haclus -modify PreferredFencingPolicy Group
Set the value of the group-level attribute Priority for each service group.
For example, run the following command:
# hagrp -modify service_group Priority 1
Make sure that you assign a parent service group an equal or lower priority than its child service group. In case the parent and the child service groups are hosted in different subclusters, then the subcluster that hosts the child service group gets higher preference.
Save the VCS configuration.
# haconf -dump -makero
# vxfenconfig -a
To disable preferred fencing for the I/O fencing configuration
# vxfenadm -d
# haclus -value UseFence
# haconf -makerw # haclus -modify PreferredFencingPolicy Disabled # haconf -dump -makero