On Wed, Jun 05, 2002 at 12:52:50PM -0700, Matthew Jacob wrote:
  | 
  | Hmm. Very interesting. Thanks.
  | 
  | The drives that are failing for me negotiate at an intermediate rate between 5
  | && 10MB/s:
  | 
  | sd0 at scsibus0 target 0 lun 0: <SEAGATE, ST31200N SUN1.05, 9424> SCSI2 0/dire
  | ct fixed
  | sd0: 1006 MB, 2700 cyl, 9 head, 84 sec, 512 bytes/sect x 2061108 sectors
  | sd0: sync (124.0ns offset 15), 8-bit (8.064MB/s) transfers, tagged queueing
  | sd1 at scsibus0 target 1 lun 0: <SEAGATE, ST1480   SUN0424, 7516> SCSI2 0/dire
  | ct fixed
  | sd1: 411 MB, 1476 cyl, 9 head, 63 sec, 512 bytes/sect x 843284 sectors
  | sd1: sync (200.0ns offset 15), 8-bit (5.000MB/s) transfers
  | sd2 at scsibus0 target 3 lun 0: <MICROP, 2217-15MQ1091501, 4930> SCSI2 0/direc
  | t fixed
  | sd2: 1683 MB, 2372 cyl, 15 head, 96 sec, 512 bytes/sect x 3447008 sectors
  | sd2: sync (124.0ns offset 15), 8-bit (8.064MB/s) transfers, tagged queueing

I've been having similar problems with an SS5 of mine with esp.
The dodgy disk in question is:
	sd0 at scsibus0 target 3 lun 0: <QUANTUM, VK4550J  SUN4.2G, 8600> SCSI2 0/direct fixed
	sd0(esp0:3:0): max sync rate 8.06MB/s

If I disable sync & tags, it works.

Also, I suspect your December 2000 kernel was before rev 1.67 of
ncr53c9x.c (Tue Dec 19 14:08:17 2000 UTC), which fixed up the sync
negotiation stuff.

Damn crap drive firmware.

Luke.