AIX 6000 BACKUP PROBLEM 2

[SCLEM30]

I HAVE A BACKUP THAT GIVES ME AN I/O MESSAGE WHEN I TRY TO READ IT. THE MAIL MESSAGE TO ROOT FROM DAEMON SAYS THE BACKUP WENT FINE. I CAN TAR FILES TO IT AND READ THEM THAT WAY. BUT EVERY TIME I USE THE BACKUP.SHL I RUN INTO THIS PROBLEM. NOW, I WORK WITH TWO SEPARATE RISCS AND THE BACKUP SCRIPTS ARE THE SAME. ALSO, I CAN READ THE BACKUP TAPE FROM THE OTHER RISC ON THIS MACHINE. BUT BUT WHEN I TAKE THE TAPE FROM THE PROBLEM MACHINE I CAN'T READ IT ANYWHERE WITHOUT AN I/0 PROBLEM. OK,, THAT HAS BEEN THE MAIN PROBLEM HERE IS THE SECOUND PART THAT THROWS A LITTLE WRENCH IN IT. IT SEEMS TO BE AN INTERMITENT PROBLEM. THE LAST TIME I TRIED THIS BACKUP UP I COULD READ IT ON THE PROBLEM MACHINE BUT NOT ON ANY OTHERS. IF THIS MAKES SINCE TO ANYONE. PLEASE LET ME KNOW.

 

[AndyBo]

Makes some sense, so here's a few thoughts...<br>
<br>
You said: &quot;The mail message to root from daemon says the backup went fine&quot;<br>
<br>
This could be a result of the script not checking for errors. For example:<br>
<FONT FACE=monospace><br>
rm /this/file/does/not/exist<br>
echo &quot;File removed OK&quot;<br>
</font><br>
And now with error checking:<br>
<FONT FACE=monospace><br>
rm /this/file/does/not/exist<br>
if [ $? != 0 ]<br>
then<br>
echo &quot;Could not remove file!&quot;<br>
else<br>
echo &quot;File removed OK&quot;<br>
fi<br>
</font><br>
I think your backup script may be echoing a &quot;everything went fine message&quot; without checking if it actually did... It's worth checking your backup script to make sure it error checks in this way.<br>
<br>
Second point is that you can read the tape on the original machine, but not on any others. Do you have hardware compression turned on on the &quot;problem&quot; box but not on the other? Or vice versa? You can check this by looking at the device details in <FONT FACE=monospace>smit</font>.<br>
<br>
Finally, are you 100% certain that the backup scripts are the same across the two machines? Copy both of them to /tmp on one of the machines (with different names, obviously ;^) and do a <FONT FACE=monospace>diff</font> on them. It could be that one of them has been changed, for example, to use cpio. Or maybe different <FONT FACE=monospace>tar</font> block sizes. Worth checking.<br>
<br>
Hope this helps.

 

[SCLEM30]

Thanks alot.. your info gives me somewhere to start I will check those things out.

 

[AndyBo]

Let us know how you get on

 

[ElgisRamon]

Did you checked the block size for the /dev/rmt0 or whatever?<br>
<br>
May be the machines have different 'default' block sizes for the tape units...<br>
<br>
I hope it works.