Not sure what this has todo with Storage Foundation ?
This is "normal" admin stuff .......
OK, so the main thing is that the tape drive will always have a device file (something like /dev/rmt or ... depends on the OS)...
Once you know what this device is, you can share it (yes, NFS .. another System Admin thing ...)
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There is a NetBackup product as well that allows you to mount data "on demand" ... this product is called (or used to be called .. not sure ... how about the NetBackup forum ??) "hierarchical storage management". If you use HSM, you can share any Veritas filesystem with this and share it ....