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, group-based race policy, or site-based policy. If you disable preferred fencing, the I/O fencing configuration uses the default count-based race policy.
Preferred fencing is not applicable to majority-based I/O fencing.
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 sys1 five times more weight compared to sys2, run the following commands:
# hasys -modify sys1 FencingWeight 50 # hasys -modify sys2 FencingWeight 10
Save the VCS configuration.
# haconf -dump -makero
Verify fencing node weights using:
# vxfenconfig -a
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
To enable site-based race policy, perform the following steps:
Make the VCS configuration writable.
# haconf -makerw
Set the value of the cluster-level attribute PreferredFencingPolicy as Site.
# haclus -modify PreferredFencingPolicy Site
Set the value of the site-level attribute Preference for each site.
For example, # hasite -modify Pune Preference 2
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