Hi,
if the Apple Xserve Storage device is detected as a drive by the OS, then you can create Backup to Disk Folders with the help of Backup Exec
if the remote Apple XServe is running MAC OS X operating system, you could install the MAC agent
The Backup Exec installs Macintosh and UNIX Agent files are copied automatically during installation from the Backup Exec installation CD to the appropriate subdirectory in Program Files\VERITAS\Backup Exec\NT\Agents on the media server.
Also, check if the Configuration is compatible:
http://support.veritas.com/docs/251810
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