fbackup fail - output file /dev/rmt/0m is not a valid device file for backup

[Tan Shirley]

Hi,

Anyone has any idea why my fbackup failed?
I received the following

br_backup: Invoking fbackup. See /var/sam/log/br_log for details.
fbackup(1004): session begins on Fri Jul 18 01:30:01 2003
fbackup(3038): output file /dev/rmt/0m is not a valid device file for backup
fbackup(3019): would you like to enter a new output file?
fbackup(3004): writer aborting
fbackup(1002): Backup did not complete : Reader or Writer process exit

Have tried replacing with another working tape drive but still failed.

[Michael Tully]

It could be that the device file has been overwritten.

Please supply:

# ls -l /dev/rmt/0m

# ioscan -fnkC tape

[Sridhar Bhaskarla]

Hi Tan,

Do some testing to see if the tape device file is correct.

mt -t /dev/rmt/0m rew
mediainit /dev/rmt/0m

Find out the correct device by using the command

ioscan -fnC tape

-Sri

[Tim Adamson_1]

Check using ioscan -fnC tape.
Check lssf /dev/rmt/* and ensure hardware path is not question marks (ie, ???)
Ensure tape drive is supported on server and server has any enablement patches installed.
Check firmware.
Clean tape drive and use new tape
Test with tar.
Ensure cabling is correctly (and firmly) attached.
Check for hardware errors in cstm or for messages in syslog or event.log.

Just a few quick things that may help.

Cheers!

[Tan Shirley]

Hi Michael,

Please find the output as follows :

#ls -l /dev/rmt/0m
crw-rw-rw- 2 bin bin 205 0x003000 Jul 2 03:55 /dev/rmt/0m

#ioscan -fnkC tape
Class I H/W Path Driver S/W State H/W Type Description
=====================================================================
tape 1 0/0/1/0.4.0 stape CLAIMED DEVICE HP C1533A
/dev/rmt/1m /dev/rmt/c0t4d0BESTn
/dev/rmt/1mb /dev/rmt/c0t4d0BESTnb
/dev/rmt/1mn /dev/rmt/c0t4d0DDS
/dev/rmt/1mnb /dev/rmt/c0t4d0DDSb
/dev/rmt/c0t4d0BEST /dev/rmt/c0t4d0DDSn
/dev/rmt/c0t4d0BESTb /dev/rmt/c0t4d0DDSnb

[twang]

Try this if it works:
# tar cvf /dev/rmt/1m /tmp

[Patrick Wallek · Accepted solution]

Well, it appears that you HAD a tape drive attached at some point that was assigned /dev/rmt/0m but that drive is no longer there. Use /dev/rmt/1m in your fbackup command instead and it will work.

[Tan Shirley]

Thanks to all ! I guess i should specify /dev/rmt/1m instead of /dev/rmt/0m.
Will try and see if the backup is successful tonight.

Meanwhile, i have another HP-UX box which has the fbackup failed as well.
The /var/sam/log/br_log did reflect that the full backup started, but no exit code. But my br_index.full file wasn't updated, so I suspect the backup did not run at all.
Below is the message i got.
Any idea what went wrong ?

br_backup: Invoking fbackup. See /var/sam/log/br_log for details.
fbackup(1601): could not access -i/-e file /nfs
fbackup(1004): session begins on Fri Jul 18 02:50:01 2003
fbackup(1517): /net not backed up - 'n' option (NFS) not specified
fbackup(3203): volume 1 has been used 26 time(s)
fbackup(3024): writing volume 1 to the output file /dev/rmt/0m

[Patrick Wallek]

The last indication in the log file is that the back did start and this it is writing to the tape. The messages indicate that it could not backup /net because the switch to tell it to cross NFS mountpoints wasn't specified.

Those are warnings and your backup should be running.

[Tan Shirley]

I also share teh same thought... But when tried to restore some files, the timestamp of those files restored were much older. And some of the files could not be found on the tape 'cos they were newly created files.
Please help ! How to check what actually went wrong ?

[Michael Tully]

Unless we know the options used on the backup was taken it is a little hard to tell why. How old the backup your attempting to restore from. Is from July 18, as in previous posts?

What is in the tape header? This will tell you when the backup was taken.

# frecover -V /tmp/header -f /dev/rmt/0m

This will give you the index of the tape.
# frecover -I /tmp/index -f /dev/rmt/0m

[twang]

Does "/dev/rmt/0m" exist?
if no, you may create a link:
# ln -s /dev/rmt/1m /dev/rmt/0m
and try to test it:
- To store a particular directory:

# fbackup -f /dev/rmt/0m -i /tmp

- To recover a particular directory:
# frecover -vx -i /tmp -f /dev/rmt/0m

[Tan Shirley]

Hi Michael,

Here's the tape header...

Magic Field:FBACKUP_LABEL
Machine Identification:9000/800
System Identification:HP-UX
Release Identification:B.11.00
Node Identification:dgamfg
User Identification:root
Record Size:32768
Time:Mon Jul 21 02:50:01 2003
Media Use:-1
Volume Number:1
Checkpoint Frequency:32
Fast Search Mark Frequency:200
Index Size:12629744 26013
Backup Identification Tag:26013 1058719801
Language:

Any clue? Thanks !

[Caesar_3]

Hello!

As you can see the device of your tape is:
/dev/rmt/1m
So set to fbackup to use this device.
Also made a check to read/write to the device
(write -> tar cf /dev/rmt/1m
read(extract) -> tar xvf /dev/rmt/1m )

Caesar