The volume name by convention can have a maximum of 18 characters, of which one is an underscore (_), that leaves 17 characters. On the Secondary, the snapshots are named uniquely according to a specific naming convention so that the snapshots can be easily associated with the specific source volumes, if we want to reattach them later. The last 10 characters of the XML file that is created on the Primary and the last seven characters of the original volume name separated by an underscore are used as the volume name. This name is unique to every snapshot. For example, if the XML file name is xmlfilename and the volume name is datavol then the Secondary snapshots are named as datavol_mlfilename.

Because the XML file name is used for creating a unique snapshot name identifier, Veritas recommends that you have a unique string in the last 10 characters of the XML file name.

Refer to the Storage Foundation Administrator's Guide for additional information about VSS snapshots.