IBM LTO Drives (ATDD Driver)

[Donald G. Hicks]

Running HP_UX 11.0. It's connected to a Silkworm 2800. My Quantum/ATL P2000 is also connected to fibre switch. Everything can see each other fine (ioscan). Followed installation instruction for atdd drivers. Cannot for the life of me get the system to recognize my four drives. I can 'mc' from slots to the drives, but I can't 'mc' from drives to slots. Here's the freaky thing. During a moment of frustration, I added any and all drivers associated with tape units to the kernel and rebooted the system. Ran 'mt -f /... status' It worked. Ran 'mt -f /... offl' It worked. Moved tpe from drive to slot. It worked. Started to 'play around' with tape libary. Got an error (media not present, or simular). Stopped working again.

I'm at a complete loss.

[Leif Halvarsson_2]

Hi

I have no experience with IBM ULTRIUM drives but with HP ULTRIUM. Do IBM drives need a own driver (atdd). I use stape for HP. Does stape not work with IBM ?

[Donald G. Hicks]

Everything I've read to date seems to indicate that that IBM ULTRIUM TD-1 use the atdd driver.

[Gerrit Beyken]

Hi Donald,

we are using the atdd Driver for our IBM LTOs too.
Thats the only choice you have if you want to backup your data to these devices in a stable way.
Until you have installed your atdd driver the tape was claimed to the stape driver which will not correctly work with your IBM LTOs.
I would suggest doing the following:
make an "ioscan -fnC tape" and take a look for your LTOs.
The line should be as this:
tape 1 1/0/2/0/0.1.24.255.0.0.2 atdd CLAIMED DEVICE IBM ULTRIUM-TD1
/dev/rmt/1m /dev/rmt/1mnb /dev/rmt/c22t0d2BESTn
/dev/rmt/1mb /dev/rmt/c22t0d2BEST /dev/rmt/c22t0d2BESTnb
/dev/rmt/1mn /dev/rmt/c22t0d2BESTb
Now take a look at your Hardware.
Are there any media in the tapes?
Are the media you want to use in the Lib?
Load a valid media to your Drive and try to make a tar on it.
If it is working do an unload by "mt -f off".
Now put the media back in Lib-Slot by using mc e.g..

Best regards

Gerrit Beyken

[Gerrit Beyken]

Hi Donald,

i just seen your ioscan (little bit too late) and everythings seems to be ok!
But i would recommend you to separate your disks and your tapes by using the second FC-Controller for Lib. including the tapes.
The best way would of course be too use a third Controller for your Lib and two Controllers for your disks to use alternative pathing.

Best regards

Gerrit Beyken

[Donald G. Hicks]

Hi Garrit,

Thanks for responding.

I'm intrigued by your answer. Right now the second FC controller is connected to disk SAN and use's failover software.

Secondly, I'm a little new at this HP admin stuff. So, please be patience, and assume I know nothing...well almost nothing :-)

Questions:

1. I know some things don't make sense, but why would putting the lib/tapes on a separate FC controller make a difference. I thought that each controller could handle 254 devices. If it works, great; but I am curious about what your experience has taught you.

2. Do I 'reattach' the library to the second card by assigning a new zone to the wwn of the second card?

Thanks,
Donald

[Angus Crome]

A note on the function of mt.
I just installed my IBM 3584 and started playing with it (all fibre attached). I have no problems with the stape driver, however, it doesn't seem to perform any hardware compression, so all I get is the native 15Mb/s.

I am going to try out the atdd driver and see if my performance increases (hope so).

As for the strange function with your tape library. Do you have labels on your tapes? I could not use my drives in the library, until I had labels on them. Don't know if it applies to your tape library or not.

The reason some people are recommending a seperate channel for your tape from your disk is for in-production data transfer. If you are running a system hot and also trying to backup your data, you will saturate a shared pipe for disk and tape.

[Gerrit Beyken]

Hi Donald,

the first of your question is already answered by Angus. This will work but it might be an performance issue.
You mentioned that your second controller is connected to your Hitchi also and uses failover software.
I`m not a specialist in hitachi`s failoversoftware but i assume that this will place over the disks that the OS is seeing (in this case it has to be a minimum two pathes for each disk)and will create another logical device.
But i don`t see disks on your second Controller (0/12/0/0). Little bit strange to me. You may want to check this with an Hitachi CE.
Your second question:
Yes i would recommend you to create a backup zone and put only your Backupdevices (your Lib. + Drives and future Devs.).
So you will see on the second card only your Backupdevs.
Hope by answers are clear to you because my
english is not the best.

Best regards

Gerrit Beyken