tar problems with Mountain 150Mb

[Mark Citron]

We have been having intermitent problems with our nightly,
unattended tar backups. We are using an AST 386/33 machine with
12Mb of memory and are running SCO 3.2.0 with tcp/ip. We backup onto
a Mountain Filesafe 7150 which is a 150 Mb drive. 

Usually after a reboot tar will work fine. After one to four
successful backups tar will fail and continue to hang (with cannot open
/dev/rct0) as an unkillable process. The only way out is to reboot. On some 
occasions tar will return "cannot open /dev/rct0" but if left running will
start the tar somewhere in the middle of the filesystem and will finish
successfully (with only some files backed up). I redirect tar output to a
file so I can monitor what it did the previous night.

I have heard some similar comments about Archive drives. Does anyone else
have similar problems with Mountain? Can anyone suggest a solution?
SCO thinks we have a DMA conflict but I cannot find anything wrong. We are
using DMA 1 for the tape with all the standard default addesses.
SCO's next suggestion is to remove ALL my drivers (ethernet, equinox-serial
ports, etc) which is too painful to think about.

Thanks for any suggestions,

-- 
Mark Citron
mark at neurosci.usc.edu