Replacing Tape Drive Configuration

[Torsten.]

The driver detects a new WWN for the same nPartID and prevents a login for safety reasons.

With the fcmsutil command you disable this check, hence the login is successful and you can use the device.

After a reboot the driver does not remember the old WWN, so this works too.

[Ralf Loehmann_2]

Hello Bala,
All good answers, here something I added to a similar question and also to a thread explaining the way better and I want to give the credit to that people:
In HP-UX under 11.31 the device file for a Device in the SAN uses a combination of the WWN and the Serial number of the Device (inquiry page 83). This means if one or the other is changed the device file identification is changed. The idea behind this is HP-UX is always on and you want to change for example your tape library to a different switch in the SAN you just change zoning and than move the device to the new ports. On HP-UX you might not need to change something in that case. Bad thing on a repair the one or the other is changing and you need to fix that.
Here is a better thread which explains what to do and also there is background information about the command in the whitepaper link. Also it works to reboot, but that is something an HP-UX customer does not like.
http://forums13.itrc.hp.com/service/forums/questionanswer.do?admit=109447627+1294224152320+28353475&threadId=1373467
Regards,
Ralf.

[Bala C]

Hi Folks,

fcmsutil replace_disk was awesome and it detected the changed drives in 11.23 servers.

I have two 11.31 servers, I faced issue in one server using the scsimgr replace_wwid -D dsf

whereas the other this command fixed.

64000/0xfa00/0x18
0/0/6/1/1.0x500e09e00aef7310.0x0 0/0/6/1/1.1.19.255.0.0.0

# scsimgr -f replace_wwid -H 64000/0xfa00/0x18
scsimgr: Successfully validated binding of LUN paths with new LUN.

# ioscan -fnC tape |grep stape
tape 11 0/0/6/1/1.1.19.255.0.0.0 stape NO_HW DEVICE HP Ultrium 3-SCSI

As you see the above output, the scsimgr replace_wwid command hasn't fixed the issue.

I also ran scsmgr replace_leg_dsf


# avoriaz:root /root# scsimgr replace_leg_dsf -D /dev/rtape/tape6_BEST
Do you really want to replace? (y/[n])? y
scsimgr: Legacy device file '/dev/rmt/c31t0d0BEST' binding to LUN changed successfully

# avoriaz:root /root# ioscan -fnC tape |grep stape
tape 11 0/0/6/1/1.1.19.255.0.0.0 stape NO_HW DEVICE HP Ultrium 3-SCSI


Is there any other option? Or Am I doing a mistake somewhere?

Kindly help.

Or Reboot the only option?

Thanks.