According the released documentation I believe this still to be true, if not please let me know. The assumption is this is an existing master server you are attempting to cluster. If not please explain.
Changing the master server host name is not a trivial task. Media server connectivity is only the beginning when changing the core component "brain" who has the host name stored in the catalog, and configuration files. See the following documents for Symantec recommendations. I'd suggest looking to your VAR or Symantec for scheduling services to accomplish this.
NetBackup high availability administration guide:
ftp://exftpp.symantec.com/pub/support/products/NetBackup_Enterprise_Server/340139.pdf
About NetBackup with clustering solutions limitations
The following general limitations exist for NetBackup in a cluster:
■ NetBackup does not support the conversion of an existing non-failover
NetBackup server to a failover NetBackup server. Contact Symantec Enterprise
technical support .
■ All NetBackup nodes within a cluster must be of the same server type and
version.
■ NetBackup is not supported as an active/active application in a cluster.
■ NetBackup Server is only supported with Microsoft Cluster Server and Veritas
Cluster Server for Windows.
PureDisk:
http://seer.entsupport.symantec.com/docs/345829.htm