[Veritas-bu] drive problems

we have a tape jukebox w/ 2 drives, and for some reason one drive gets
frequent i/o errors and often fails to read/write/eject tapes.

Here's a smpling of the errors:

10/25/2001 12:20:10 bp83 cc4  cannot write image to media id 000073, drive
index 0, I/O error
10/25/2001 12:20:12 bp83 cc4  backup of client cc4 exited with status 84
(media write error)
10/25/2001 12:20:49 bp83 bp60  archive by root on client bp60 using sched
User-Archive:  unable to process request                    because the
server resources are busy
10/25/2001 12:29:56 bp83 cc4  media id 000073 is in a DOWN drive,
misplaced, write protected or unmountable;
                    attempting retry with a different media id
10/25/2001 12:39:58 bp83 ptdb  archive by root on client ptdb using sched
User-Archive:  unable to process request                    because the
server resources are busy
10/25/2001 14:00:05 bp83 cc4  media id 000073 is in a DOWN drive,
misplaced, write protected or unmountable;
                    attempting retry with a different media id
10/25/2001 14:23:55 bp83 bp1  cannot write image to media id 000042, drive
index 1, I/O error
10/25/2001 14:23:56 bp83 bp1  archive by root on client bp1 using sched
User-Archive:  media write error


output from tpconfig -d:

# tpconfig -d
Index DriveName              DrivePath                Type   Multihost
Status
***** *********              **********               ****   *********
******
  0   SONYSDX-500C0          /dev/rmt/0cbn            8mm      No
UP
        TL8(0) Definition       DRIVE=1
  1   SONYSDX-500C1          /dev/rmt/1cbn            8mm      No
UP
        TL8(0) Definition       DRIVE=2

Currently defined robotics are:
  TL8(0)     robotic path = /dev/sg/c1t3l0, volume database host = bp83


Some entries from /var/adm/messsages:

Oct 25 12:05:10 bp83 scsi: [ID 107833 kern.warning] WARNING:
/sbus@1f,0/SUNW,fas@1,8800000/st@1,0 (st8):
Oct 25 12:05:10 bp83    Error for Command: write                   Error
Level: Fatal
Oct 25 12:05:10 bp83 scsi: [ID 107833 kern.notice]      Requested Block:
779878                    Error Block: 779878
Oct 25 12:05:10 bp83 scsi: [ID 107833 kern.notice]      Vendor: SONY
Serial Number:
Oct 25 12:05:10 bp83 scsi: [ID 107833 kern.notice]      Sense Key: Media
Error
Oct 25 12:05:10 bp83 scsi: [ID 107833 kern.notice]      ASC: 0x52
(cartridge fault), ASCQ: 0x0, FRU: 0x0
Oct 25 12:15:00 bp83 heartbeat: [ID 702911 daemon.notice] 12:15pm up 23
day(s), 19:11, 3 users, load average: 0.19, 0.28, 0.50
Oct 25 12:20:49 bp83 tl8cd[5239]: [ID 251588 daemon.error] TL8(0)
move_medium error
Oct 25 12:20:49 bp83 tl8cd[5239]: [ID 141418 daemon.error] TL8(0) Sense
Key:  Illegal Request (5h)
Oct 25 12:20:49 bp83 tl8cd[5239]: [ID 213999 daemon.error] TL8(0) ASC 3bh,
ASCQ 90h
Oct 25 12:20:49 bp83 tl8d[212]: [ID 550331 daemon.error] TL8(0) drive 1
(device 0) is being DOWNED, status: Robotic dismount failure
Oct 25 12:20:49 bp83 tl8d[212]: [ID 229259 daemon.error] Check integrity
of the drive, drive path, and media





I've got no idea why it keeps happening.  Are there any causes other than
just having bad hardware ? The tape drive was swapped out for a new one
less than a month ago.

Thanks,
Nicholas