Termination(?) problems w/ 5.1.0pre10 (& earlier)

[Doug Ledford]

> aic7xxx: Cables present (Int-50 YES, Int-68 YES, Ext-68 NO)
> aic7xxx: EEPROM is present.
> aic7xxx: SE High byte termination Enabled

> I tried setting termination using the BIOS utility to HIGH on, LOW off.  This
> got rid of the medium errors, but the CD-ROM and tape drive would drop offline
> while the system was running.  I went back to auto-termination, and now I'm
> getting these again:

The termination both before and after your changes is identical.  There is
no difference in the final outcome between these two configurations.

> scsi0: MEDIUM ERROR on channel 0, id 0, lun 0, CDB: Read (6) 17 4c 44 08 00
> Current error sd08:03: sense key Medium Error
> Additional sense indicates Unrecovered read error
> scsidisk I/O error: dev 08:03, sector 691474, absolute sector 1526854
> 
> The correlation between type of termination and the frequency of these errors
> seems too good for this to be coincidence.

Well, for termination problems the bus usually either hangs or we see parity
errors on the bus.  We *don't* see device reported unrecoverable read
errors.  This is coincidence, even if it is hard to believe.  If you want to
find out for sure, try setting termination to high on, low off (which you
say gets rid o fthe medium errors) and then boot to single user mode.  With
the system in single user mode and the filesystem mounted read-only, run
e2fsck -c on your partition.  Then wait and see, I bet you get medium
errors.

-- 

 Doug Ledford  <dledford at dialnet.net>
  Opinions expressed are my own, but
     they should be everybody's.

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