jht@suned1.Nswses.Navy.MIL (James H Tibbs) (09/20/90)
We have an DILOG Exabyte attached to a MV 3600 (VMS 5.2) via
a DILOG controller. The unit is advertised as one which emulates
a TK50. Originally, the unit would not allow multiple BACKUP
save sets on the same volume. An upgrade to the "G" ROM chip
fixed this. The current major problem is that the unit does not seem
to know how to do backups spread across multiple volumes (tapes).
Specifically, during the *verify* pass BACKUP will report (seems
to find end of tape during the original, data recording pass);
BACKUP-F-POSSITERR, error positioning MUC0:[]sar2b.bak;
-SYSTEM-F-DATA-LOST, data lost
An "analyze/error/inclue=muc0" shows recorded errors in the
"intervening records at EOF" section such as;
"SEQUENCE NUMBER RESET"
"UNRECOVERABLE ERROR"
"DRIVE ERROR"
"DRIVE COMMAND TIMEOUT"
"DATA ERROR"
"LONG GAP ENCOUNTERED"
If a verify switch is left out of the BACKUP command
a multivolume save set will work *some* of the time. (the exabyte
is exhibiting some other flakyness at random times. Somtimes it
has problems positioning the first, and only, save_set on a tape).
The unit will, less frequently, lose its position on a backup,
less the verify, which does not cross tape boundaries.
In response to the current problem the tape unit itself was
replaced by the manufacture ( who claimed that our original
unit checked out OK under their diagnostic procedure).
The replacement unit allowed me to write three save_sets
(about 650 MB each) to it, the third of which extended to a
second volume......apparently without error. To "confirm"
that the save sets were all there and looked to be of
reasonable size I mounted the tape as a Files-11 device
( mount muc0 exbtst )and did a "DIR/SIZE". At the appro-
priate time I was asked to mount the second relative
volume (label = "EXBT02") and did so along with a proper
REPLY. BACKUP could not recognize the second volume as
being labeled "EXBTO2", however..............a mount/for
on the second volume did show that its label was indeed
"EXBT02".............weird!..........:-(
Thinking bad tape, we use Sonys, I made a new run only
to encounter the same problem we had before replacing the
tape unit; verify barfs on save sets which extend across
multiple volumes.........?
QUESTION: Has anyone else encountered similar problems with
this exabyte on a MV3600? Fixes? We have been told that such
problem w/exabytes were common under VMS 5.2 but not 5.3...?
I am relatively new to the VMS game and have dumped many GB to
this unit and mucked with the BACKUP switches quite a bit in
trying to eliminate "OPER" error; even tried the old UNIX trick
of rebooting the machine a couple of times.......and yes, I have
talked to the vendor. Nonetheless, any constructive flames, hints,
ideas greatly appreciated.
Thanks in advance!
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