DAT Autoloader script?

[CKT]

Hi,

I have a HP DAT Autoloader with 6 DDS slots. I was wondering if anyone has written any shell script (perhaps using a combination of tar and fbackup commands) to backup data to each individual DDS tape without using Omniback or Netbackup? Is it possible to create a device file for each slot and command the autoloader to swap tape from a script?

Jules

[Manju Kampli]

there is a utility "mc" Media changer which can be used to load and unload the tapes from the slots to the drive. you can use this along with your fbackup/tar command which will take tape from each slot and take backup accordingly. use man pages of "mc" for more options.

Manju

[Armin Geisbusch]

Hello!

Where can I get the mc "Media Changer" Tool?

Best regards, Armin

[Patrick Wessel]

Armin,

mc is part of hp-ux and it's /usr/sbin/mc
The man page tells you some more details

[Andreas Voss · Accepted solution]

Hi,

here an example:

mc -p /dev/autochanger_spt -s S1 -d D1
tar cvf /dev/rmt/0m .....
mc -p /dev/autochanger_spt -s D1 -d S1 -s S2 -d D1
tar cvf /dev/rmt/0m .....
mc -p /dev/autochanger_spt -s D1 -d S2

The above example will load DDS from Slot 1 into drive, then do tar backup.
After this it unloads the DDS from drive to Slot 1 and load DDS from Slot 2 into drive.
Then do again tar backup.
Finally unload DDS from drive into Slot 2.
The /dev/autochanger_spt must be the scsi pass through device driver for your autochanger (Ie.: major=76 minor=0x053100).
You must have the driver spt in the kernel!

Regards

Andrew

[CKT]

Thank you all for the info. Does anyone know the different between these drivers?
spt
sctl
schgr
stape
Are they are needed for the DDS4 DAT autoloader?

Also, when you use fbackup and tar to back up to the autoloader how do you know the embedded tape is full in order to swap a second tape in? Is there a command to query how much space is left on the tape?

Thanks.

[Philip Chan_1]

In your fbackup config file you can specify a script to run when hitting the end of tape. Have a look at /etc/sam/br/fbackup_config and the parameter should be "chgvol". Also, do "man fbackup" and you'll see some simple examples.

Rgds,
Philip

[Bill Hassell]

Armin wrote:

"Where can I get the mc "Media Changer" Tool?"

Answer: PHCO_16194 for 10.20

[Glenn S. Davidson]

I had a couple of systems where I had an AL-48 (i think that was the model) attached and I created a whole bunch of backup scripts using fbackup and the 6 slot changer. Email me if you're interested in looking at them.
gglom@bigfoot.com

[Dragan Krnic]

There is a disadvantage to using mc - execution of any of its subcommands puts the drive into random mode. The normal sequential mode can only be restored by reinserting the tapes container.

If you really need to strictly separate the backups on per-tape basis then you need to use mc but a more straightforward processing can be achieved by using the changer in its default mode. In this mode the "mt offl" command will automatically insert the next tape so it's easier to continue a multi-tape backup.

There was a neat backup utility by www.adiva.de called xb/xr that used to handle such problems elegantly. It produced tar, cpio or dump formats, full volume or selective path/date-wise, with a directory up front which could be used to inspect the contents in any terminal window and retrieve individual files/directories by spacing forward directly to selected files.Upon reaching the end of tape it would eject the full tape and poll the device every 30s if a fresh tape is available to continue the backup.