how big can etc get anyways? mine's 30MB...
My only caution would be to remind people that dump and restore create temporary files in the /etc/tmp directory when they run.
In the case of restore of a large backup, the temporary files can grow into the GBs.
You could make a rough estimate of about 256 bytes per file on tape during a full or single-file/subtree restore....
For the backup, estimate about 6 bytes per inode (by total inodes, not by allocated inode).
Stephen Manley Data Availability and Management Movie Reviewer
P.S. Go see Titan A.E. Not as good as Iron Giant, but better than the latest Star Wars...