henry (05/10/83)
After a lengthy work session by Terabit Friday and today, the old drive now appears to be pretty much functional again. The only thing that really is wrong with it now is a tendency to get timeouts when it runs into a bad spot on the surface. This happens at a few places which are known to be bad spots on that pack; oddly, it doesn't happen at other spots known to be bad. Terabit replaced some heads among other things, so perhaps the head alignment is off. This would explain the thing noticing some old bad spots and not others. More testing to come.
henry@utzoo.UUCP (Henry Spencer) (05/27/83)
Based on tests run yesterday, it now appears that the source of our long-standing problems with the old drive may well have been the pack(s) rather than the drive. Our old Memorex packs seem to be in lousy shape, with a strong suspicion of servo-surface damage. The standalone drive diagnostics run just fine on the old drive using one of Terabit's Dysan scratch packs, but they really choke on one (either one) of our old packs. The only serious test left to be run is to try moving our current production pack (the new Dysan) to the old drive. If we run on this for a while with no problem, QED. We'd tentatively planned to do this sort of thing anyway, to assess whether all the old drive's problems had been fixed. Pack switch (and the minor bit of cable shuffling to make the old drive drive #0 again) will probably be done during Monday backups.
henry@utzoo.UUCP (Henry Spencer) (10/17/83)
Well, things did not go exactly as planned today. Terabit screwed up,
and Matt showed up shortly after noon instead of first thing in the
morning. (To his credit, he sounded as angry about this as we were.)
To avoid a long downtime rather later in the day than we had planned,
we modified the original plan. Matt checked out drive A (the old one),
left us the loaner pack, and carted away the unused bad pack. We will
now format/test the loaner and then do the pack-to-pack copy to get
the production system moved to drive A and the loaner pack. Once that
is accomplished, Matt will return to check out drive B and haul away
the other bad pack.
For this I got up five hours early?
--
Henry Spencer @ U of Toronto Zoology
{allegra,ihnp4,linus,decvax}!utzoo!henryhenry@utzoo.UUCP (Henry Spencer) (11/23/83)
Well... here we go again. Matt came in, did PM on drive A, found things
really sick inside. After open-heart surgery, we started testing. SELECT
LOCK. There were various fudgings around with the cables; the current
status is that we have run the drive ok with the old cable run through the
cable slot but not yet routed under the floor. Matt, however, is not
yet convinced that the drive is fully repaired. He has taken away two
boards, to return late tomorrow afternoon (exact time TBA).
Argh.
--
Henry Spencer @ U of Toronto Zoology
{allegra,ihnp4,linus,decvax}!utzoo!henry