topic Re: mc commands in Operating System - HP-UX

mc commands

hpuxrox — Tue, 17 Sep 2002 18:28:47 GMT

Does anyone know if the mc command can be ran while omniback is running.

like,

mc -p /dev/robot -r DIMS

to just query the drive and slots.

Or is there known issues with this?

Re: mc commands

Ted Ellis_2 — Tue, 17 Sep 2002 18:32:44 GMT

I don't think this would create a problem as it is just pulling information from the robot on status... not physically moving tapes of the robot. You can manually perform operations via the front panel of libraries while OmniBack is running as well.... should be OK.

by the way.... command should be

mc -p /dev/robot -r IDMS

Re: mc commands

John Poff — Tue, 17 Sep 2002 18:33:44 GMT

Hi,

Sure. I've used it before while OmniBack was running. We use it to unload DLT tape drives remotely (dialed in during the middle of the night) when they hang with a tape in the drive. I guess you could hit a snag if OmniBack is using the robot when you issue an 'mc' command, but my guess is that 'mc' would return with an error and you could just try it again.

JP

Re: mc commands

A. Clay Stephenson — Tue, 17 Sep 2002 18:37:12 GMT

As long as you restrict yourself to query commands these are safe; don't do any move commands.

You can also use the uma command to do a 'stat' or an 'inq' command.

Re: mc commands

Ted Ellis_2 — Tue, 17 Sep 2002 18:39:48 GMT

a word of caution if using this to actually move tapes around... make sure you update the OmniBack media information with a barcode scan so OmniBack knows what changed.... otherwise you could run into a problem where tapes are out of sequence, etc.

Re: mc commands

hpuxrox — Tue, 17 Sep 2002 18:47:26 GMT

Thanks, I understand the issues with moving tapes while omniback is still aware of its location somewhere else.

I was just told that the command itself (even query) can cause the robot to panic if omniback is running. Like I was told 6 months ago that ioscans will cause disks to hang. I cant keep giving up my tools or ill never be able to fix anything :-)

Re: mc commands

Michael Tully — Tue, 17 Sep 2002 22:40:30 GMT

One handy thing I found with using 'mc' to do queries is that reports the barcode number.
Some other examples of moving tapes around, although a dangerous exercise if you don't do a barcode scan afterwards. Other than keeping your tape library and omniback in sync with each other and if you reset you tape library you will get an error message if you attempt to use it before it has finished it's selftests, there are no known issues.

Move a tape from slot 10 to mailslot slot 1
# mc -p /dev/robot -sS10 -dI1

Move tape from mailslot slot to slot
# mv -p /dev/robot -sI1 -S10

Re: mc commands

Bill Hassell — Wed, 18 Sep 2002 01:27:20 GMT

One note about ioscan: ALWAYS use -k option to avoid the extensive delays seen when querying devices. There is no reason to leave off the -k option unless you are connecting peripherals with power on (definitely not recommended). And ioscan -k is 50-200x faster (it just reads the kernel tables).