-----Original Message----- From: Farren Minns [mailto:[EMAIL PROTECTED]] Sent: Monday, January 28, 2002 6:20 AM To: [EMAIL PROTECTED] Subject: A few basic TSM questions
Hi TSMers I wonder if you can help with a few, hopefully simple, questions. I am running TSM 3.7.3.8 server on a Solaris 2.7 server (E250 400mhz with 1GB Mem) . This is connected to an IBM 3494 library with two 3590 tape drives. Most of our clients are either Sun or NT boxes running client level 3.7.2.0 (only about 28 client nodes in total). Question 1) We have a situation where an external user wants to be able to perform restores as and when necessary. At present, I prefer that all restore requests come through us so that we can keep track of who's doing what on our machines (particularly our backup server). However, let's just say that I wanted to allow a user access to backing up and restoring relevant files; how do I restrict that user to just certain files / file systems etc. i.e. how do I make sure that a user does not have free run of the box? >>> Look at the dsm.sys file. You can allow non-root users to run the dsm process by including their id or group name. WHen they start dsm as a non-root user, dsm honors the standard UNIX permissions; they can only restore files they would normally have WRITE access to. Same is true for Windows NT; the TSM client gives them access to whatever files NT normally gives them access to (although I personally have not tested that since the 3.1.0.6 client). Question 2) During the day we tend to run tape reclamation of our Tapepool and Copypool. Also, Expiration kicks in at 24 hour intervals and takes about 30-45mins to complete. Reclamation can take several hours. What I'm interested in is what happens when a restore is requested when either of these processes is running. Can TSM cope with this? If the restore needs to access a tape but both tape drives are in use with reclamation, will the restore take precedence, or will it sit and wait until a tape drive becomes available? >>> If a user requests a restore and there is no tape drive available, TSM is SUPPOSED to knock down one of the other processes and give the RESTORE the drive. I've seen it work, and I've seen it NOT work at 3.7.4 on our AIX TSM server. I've frequently seen it kill a reclamation to give a RESTORE a tape drive, but occasionally it doesn't'; I've always suspected the "doesn't" case is due to a data base lock, or maybe the user needs the specific tape that is being reclaimed, or something like that. If a restore is requested and expiration is running, does this have a negative / damaging effect on the server? >>> There is no damaging effect on the server when other stuff runs during expiration. Sometimes you may see an error message about a lock not being acquired; that is a harmless message that just indicates there was a conflict between the two processes, and TSM has locked one out. But TSM will cope. >>> On the other hand, remember that expiration is VERY DB I/O intensive; it can slow down performance considerably, and in my case we found that the recovery log gets DANGEROUSly full if we run RECLAMATION and EXPIRATION at the same time. But you may not have that problem; just depends on whether you get the performance you want. Question 3) Should expiration be run when no other processes are active, or does TSM cope either way? Any help will be very much appreciated. Kind Regards Farren S Minns (Trainee Solaris System Admin - John Wiley & Sons)
