[9fans] adm. pseudo-WORM fs

[forsyth@caldo.demon.co.uk forsyth@caldo.demon.co.uk]

>>Who uses pseudo-WORM jukebox?
>>How do you back up the pseudo-WORM, just use scuzz to 8mm tape?

i use a pseudo-worm (on a 4Gb IBM drive).  9fs dump is well worthwhile.
backup is done in an `allow' mode to other media
via disk/mkfs -a at the moment.

one problem is that i believe it is not straightforward
as things stand to extend a pseudo-worm.
you need to dump/reinit/restore when it fills up (losing the history).
that's what i did when i ran one at the university on a much smaller disc.
(i later switched to using a plain file system without a dump file system.)

fortunately, my current pseudo-worm is big enough that it's not a problem just
yet.

i'd quite like, however, to switch to a proper jukebox of some sort.
i'm curious what changes were required to support the HP ones,
and what other decent ones might be on the market.