I found out what was happening. Summary: We had a problem where tar seemed to be keeping a tape drive for somewhere between 5 and 20 minutes after it completed. But this only happened when using REXEC from VSE. REXEC from VM or an interactive tar from a telnet session, did not show this behavior.
While having a vmstat 10 1000 running on the machine that the tar was running on, I discovered the actual problem. The rexecd server in Linux (SLES 11 SP 1), was returning from the tar command before the command had completed. So, why the tape drive showed it was still in use, well the tar was still running. REXECD came back to VSE (a batch job) and then tried issuing additional commands, which failed due to the tape drive was still in use. Additionally, I was producing a listing of files that were being backed up. When I redirected the list of files to a disk file, the tar didn't produce any output once it started. Something...i.e. REXECD perhaps decided that the command did finish without any output and returned back to the client. When I did the same tar command and had the list of files being backed up sent back to VSE, i.e. a very active connection, REXECD didn't return back to the client until the tar was finished. Weird type of thing. I'm not really up on pipes and Linux, but in the VM world, I can pipe output to the console and to a file without blocking the stage. Is there something similar in the Linux world so I can keep the listing and keep the connection active? Thanks Tom Duerbusch THD Consulting >>> Carsten Otte <co...@de.ibm.com> 7/28/2011 8:41 AM >>> Hi Tom, if I recall correctly, we reserve the tape on open, and free it on closing the file descriptor. You shout be able to find out which process is using it via "fuser /dev/ntibmX". with kind regards Carsten Otte IBM Linux Technology Center / Boeblingen lab -- omnis enim res, quae dando non deficit, dum habetur et non datur, nondum habetur, quomodo habenda est ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/ ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
