N/A
As part of the 'vxfenswap' activity the information about the current coordinator configuration is read from the /etc/vxfentab file. Even if 'vxfenswap' is being used to change only the CP server, vxfen would need to check that the information that it has on the coordinator disks is also consistent on both nodes. If there is an inconsistency in the coordinator disk information, then the CP server swap will not proceed.
As it happens the storage name had changed, so whilst VxVM on both nodes showed the same information (ie disk names, udids, etc), it could be seen in the /etc/vxfentab and 'vxfenconfig -l' outputs that the second cluster node still had references to the old storage name and so there was an inconsistency between the two VCS nodes.
The second cluster node was rebooted and upon reboot the /etc/vxfentab file and 'vxfenconfig -l' output were now showing the same disk names on both cluster nodes. At this point 'vxfenswap' was able to successfully do the CP server switch.