topic Re: Cannot Read/Write to a tape drive. in Operating System - HP-UX

Cannot Read/Write to a tape drive.

Andre Lemon — Wed, 11 Jun 2003 12:16:02 GMT

Can anyone help with this message, all of a suddon our dds drive would error when trying to
write to a tape, as far as i know no settings
have been changed (I am not sure what they should be, so i cannot determine if they have
changed). This error happens when starting to write to the second DDS in our standard backup.
The first one wrote fine, then for some reason
the second one creates the error. This is not
isolated to the backup, this occurs when trying
to load data from a dds also. is 1m a valid file, is shows that it was created the same date and time as the backup, is that a coincidence, Any Ideas?

a listing from / # cd /dev/rmt:
/dev/rmt # ll
total 0
crw-rw-rw- 2 205 0x003000 Jun 4 14:36 1m
crw-rw-rw- 2 205 0x003080 Mar 30 2000 1mb
crw-rw-rw- 2 205 0x003040 Mar 30 2000 1mn
crw-rw-rw- 2 205 0x0030c0 Mar 30 2000 1mnb
crw-rw-rw- 2 205 0x003000 Jun 4 14:36 c0t3d0BEST
crw-rw-rw- 2 205 0x003080 Mar 30 2000 c0t3d0BESTb
crw-rw-rw- 2 205 0x003040 Mar 30 2000 c0t3d0BESTn
crw-rw-rw- 2 205 0x0030c0 Mar 30 2000 c0t3d0BESTnb
crw-rw-rw- 1 205 0x003001 Mar 30 2000 c0t3d0DDS
crw-rw-rw- 1 205 0x003081 Mar 30 2000 c0t3d0DDSb
crw-rw-rw- 1 205 0x003041 Mar 30 2000 c0t3d0DDSn
crw-rw-rw- 1 205 0x0030c1 Mar 30 2000 c0t3d0DDSnb
crw-r--r-- 1 205 0xfffffe Mar 30 2000 stape_config

Backup output message:

Wed Jun 4 13:41:03 EDT 2003
fbackup(1004): session begins on Wed Jun 4 13:41:03 2003
fbackup(3203): volume 1 has been used 44 time(s)
fbackup(3024): writing volume 1 to the output file /dev/rmt/1m

1: main.bu 13583568
fbackup(1005): run time: 3395 seconds
fbackup(3055): total file blocks read for backup: 13583568
fbackup(3056): total blocks written to output file /dev/rmt/1m: 13585241
Wed Jun 4 14:37:56 EDT 2003
Please take out the Production tape, insert the Develop tape,
wait for a solid green light, and hit return when ready

Wed Jun 4 14:37:56 EDT 2003
fbackup(1004): session begins on Wed Jun 4 14:37:56 2003
fbackup(3038): output file /dev/rmt/1m is not a valid device file for backup
fbackup(3019): would you like to enter a new output file?
fbackup(4002): please respond with: '^[yY]' or '^[nN]'

Re: Cannot Read/Write to a tape drive.

Pete Randall — Wed, 11 Jun 2003 12:23:02 GMT

Andre,

I think your 1m device file is OK. Mine have the time/date of the last backup as well:

ll /dev/rmt/?m
crw-rw-rw- 1 bin bin 205 0x000000 May 9 13:33 /dev/rmt/0m
crw-rw-rw- 1 bin bin 205 0x081000 Apr 24 2001 /dev/rmt/1m
crw-rw-rw- 1 bin bin 205 0x072000 Jun 11 00:16 /dev/rmt/2m
crw-rw-rw- 1 bin bin 205 0x063000 Jun 11 00:11 /dev/rmt/3m
crw-rw-rw- 1 bin bin 205 0x054000 Jun 11 08:42 /dev/rmt/4m
crw-rw-rw- 1 bin bin 205 0x045000 Jun 11 07:06 /dev/rmt/5m
crw-rw-rw- 1 bin bin 205 0x036000 Jun 10 21:12 /dev/rmt/6m

Have you done the usual things, like cleaning the drive, trying defferent tapes, etc.?

Pete

Re: Cannot Read/Write to a tape drive.

Keely Jackson — Wed, 11 Jun 2003 12:23:08 GMT

Hi

Have you tried cleaning the drive and/or a new tape?

Keely

Re: Cannot Read/Write to a tape drive.

F. X. de Montgolfier — Wed, 11 Jun 2003 12:35:55 GMT

Hi,

have you done an ioscan to see what your tape special files were?

For exemple,
# ioscan -C tape -fun
Class I H/W Path Driver S/W State H/W Type Description
=====================================================================
tape 0 0/0/2/0.3.0 stape CLAIMED DEVICE HP C1537A
/dev/rmt/0m /dev/rmt/c2t3d0BESTn
/dev/rmt/0mb /dev/rmt/c2t3d0BESTnb
/dev/rmt/0mn /dev/rmt/c2t3d0DDS
/dev/rmt/0mnb /dev/rmt/c2t3d0DDSb
/dev/rmt/c2t3d0BEST /dev/rmt/c2t3d0DDSn
/dev/rmt/c2t3d0BESTb /dev/rmt/c2t3d0DDSnb

If you don't find /dev/rmt/1m in these files, the special file you were writing to is not the proper one.

However, since the first part of your backup worked, it is much more likely that your tape itself was not correct:
1. are you sure that it wasn't write-protected?
2. are you sure that it's the right DDS type? DDS is not backward comnpastible, thus a DDS2 tape in a DDS drive will not work, and so on...

If the tape seems to be all right, try doing a small test: load a blank, *never used* tape, then:

# touch /tmp/foo
# tar cfv /dev/rmt/1m foo

and see if it works. If it doesn't, you may want to use a cleaning tape on your reader and start again. If after being cleaned your tape reader still refuses to work, you may have a hardware problem...

Cheers,

FiX

Re: Cannot Read/Write to a tape drive.

twang — Wed, 11 Jun 2003 12:49:57 GMT

1. to check you drive is attached:
# ioscan -fnC tape
2. use tar to save file to default tape drive file:
# tar cv /tmp
and check whether your tape drive is working
hope the above steps can help you

Re: Cannot Read/Write to a tape drive.

John Dvorchak — Wed, 11 Jun 2003 12:53:25 GMT

My 2 cents worth, in the past that error indicated that what I thought was a good tape proved not to be. Please take the other's suggestions about cleaning the drive and confirming, with tar etc., that the second tape is good.

Re: Cannot Read/Write to a tape drive.

Andre Lemon — Wed, 11 Jun 2003 12:53:33 GMT

F.X.

I did the ioscan and 1m was there. The tapes that we are using are the same as always and
we have them on a 21 day cycle and there are 4 in each set. Our scripts have not changed at
all. Again, this is not limited to the backup, we only have 2 processes that use a tape drive.... the daily backup and one monthly
load of a input file.....

Here are the results after cleaning the drive
using a new dds tape.

/
/ # touch /tmp/foo
/ # tar cfv /dev/rmt/1m /tmp/foo
a /tmp/foo 0 blocks

Re: Cannot Read/Write to a tape drive.

John Dvorchak — Wed, 11 Jun 2003 12:54:09 GMT

Re: Cannot Read/Write to a tape drive.

Shannon Petry — Wed, 11 Jun 2003 13:04:29 GMT

When the drive works for a tape or tapes, then magically fails usually this means a bad tape.

Sometimes, it is a door lock jammed open (I see this alot with 3M tapes), other times spindles could be locked (see this lots in 3rd party tapes), other times the tape is just plain bad (warped/stretched, etc..)

If you buy tapes in bulk like I do, then normally you will not have 1 bad tape from the lot but several.

Change the tape, and put aside the bad one. My distributor will credit me for bad tapes, maybe yours will too.

Sincerely,
Shannon