TAR: tape read error 1

[angelshark]

Hello,


I’m having trouble restoring data from our production server into our testing server. Both servers are identical. The utility used for backup/restore is tar and the error message is: tape read error. When we first saw this problem we replaced the HP DAT24 tape drive on the testing server with a brand new drive but the problem persists. We have used brand new tapes to backup the data on the production server but when we try to restore it on the testing server we get the same error message. We have cleaned the tape drives too.

Do you have an idea about the cause of the problem?

Thanks for your help.

 

[angelshark]

I would just like to add that the production server is running HP-UX 10.20 and the testing server is running HP-UX 11.00. When trying to restore a tape on the testing server the tape drive's leds start to blink in alternate. If I try to read the same tape on the production server, it works perfectly. Could it be a block size problem?

Thanks for all your suggestions/comments.

 

[GrahamBright]

What tar commands are you using maybe you're using the wrong device files to read the medium. The default tape device is /dev/rmt/0m so to read the medium you could use the -t option to verify that the tape can be understood.

Also what type of DAT tapes are you using, the capacity may be larger than the drive can understand see

http://h18006.www1.hp.com/products/storageworks/datdrives/qa.html

tar -tvf /dev/rmt/0m

Quick reference to tape commands


ar -tvf /dev/rmt/0m #default tape device

tar -cvf /dev/rmt/0lbn filename #put filename onto tape, filename can be a dir
tar -tvf /dev/rmt/0lbn #get a table of what's on the tape
tar -xvf /dev/rmt/0lbn /directory on new machine #extracts tape contents into current disk dir
v = verbose
f = file
tar -rvf /dev/rmt/0m <directory/filename> append to the end of archive.

c Create a new archive. Write from the beginning of the
archive instead of appending after the last file. Any
previous information in the archive is overwritten.

r Add the named file to the end of the archive. The same
blocking factor used to create the archive must be used to
append to it.


mt -f /dev/rmt/2lbn rew #rewind the tape

In sam -> see the type of tape drive that is on the sytem
tar xvf /dev/rmt/0m .

 

[raztaboule]

check the block size used on the test and production servers, if they don"t match you can expect troubles.don't know how do to that on HP-UX ( i'm from AIX ).

bye.

 

[dblair]

try using dd or pax.
see the man pages.

 

[angelshark]

I have replaced the production server's tape drive with a brand new drive identical to the one installed in the testing server and now everything works perfectly.

Thanks for all your suggestions.