Offline migration of HP Vm with tape drives attached

[Cresswell Williams]

Hi Experts

How can I migrate a HP IVM with a Tape drive as a backing store. The target host also has access to the same Tape Drive, but of course, the H/W paths to this tape drive is different on the two systems:
Here is som output:
Minimum Target Maximum
Memory Memory Memory
=========== =========== ===========
2048 MB 2048 MB 4096 MB

[Storage Interface Details]
Guest Physical
Device Adaptor Bus Dev Ftn Tgt Lun Storage Device
======= ========== === === === === === ========= =========================
disk scsi 0 0 0 0 0 disk /dev/rdisk/disk279
tape avio_stor 0 7 0 0 0 attach_path 0/3/0/0/0/0.0x100000e0022368d9.0x1000000000000
tape avio_stor 0 7 0 1 0 attach_path 0/3/0/0/0/0.0x100000e0022368d9.0x2000000000000

[Network Interface Details]
Interface Adaptor Name/Num PortNum Bus Dev Ftn Mac Address
========= ========== ========== ======= === === === =================
vswitch lan vswitch2 7 0 1 0 d6-6a-59-d6-31-04
vswitch lan vswitch3 4 0 2 0 3e-68-9c-78-9f-33
vswitch lan vswitch2 8 0 4 0 6e-f1-58-46-c3-17
vswitch lan localnet 1 0 5 0 42-79-13-d6-b8-c1
vswitch lan vswitch3 5 0 6 0 92-88-c3-19-4e-18

[Misc Interface Details]
Guest Physical
Device Adaptor Bus Dev Ftn Tgt Lun Storage Device
======= ========== === === === === === ========= =========================
serial com1 tty console
root@dps_vse_host1:/#
root@dps_vse_host1:/#
root@dps_vse_host1:/#
root@dps_vse_host1:/#
root@dps_vse_host1:/# hpvmmigrate -P node2 -h prd_vse_host1
hpvmmigrate: Connected to target host using 'prd_vse_host1'
hpvmmigrate: WARNING (node2): Remote message: Hardware path '0/3/0/0/0/0.0x100000e0022368d9.0x1000000000000' does not exist.
hpvmmigrate: WARNING (node2): Remote message: Hardware path '0/3/0/0/0/0.0x100000e0022368d9.0x2000000000000' does not exist.
hpvmmigrate: ERROR (node2): Remote message: Hardware path '0/3/0/0/0/0.0x100000e0022368d9.0x1000000000000' is invalid.
hpvmmigrate: ERROR (node2): Remote message: Hardware path '0/3/0/0/0/0.0x100000e0022368d9.0x2000000000000' is invalid.

Please give any alternative as to unpresenting the Tape Drive and then presenting it again when the migration is done.


Thank you

[Steven E. Protter]

Shalom,

Sharing the tape drive is a problematic thing to do with HP-UX.

You could not use the tape drive at all.

You can dd the entire disk or logical volume the guest sits on to a file, transfer the file via scp and then dd the file to a new logical volume somewhere else.

Lets say the hpvm guest sits on vg01/rlvol1

dd if=/dev/vg01/rlvol1 of=/tmp/myguest.file bs=640000
# Set a big block size or it will take forever

Then scp the file to a new hpvm host.

dd if=/tmp/myguest.file of=/dev/vg01/rlvol2 bs=

Note my example requires a ton of space on the /tmp filesystem. You will need to find room for this process.

This process, with a little realism will work though, I've done it.

SEP

[Francisco Mata_1]

You can change the instance number associated to the tape on each machine with "ioinit -f infile"

infile should look like as

HW_ADDRES_OF_TAPE tape Instance

run insf -eCtape

and you will have a new /dev/rmt/tapeX where X is the instance number you are assigning.

you can check device special files with ioscan -fnNCtape

[Eric SAUBIGNAC]

Bonsoir,

"but of course, the H/W paths to this tape drive is different on the two systems"

Yes ... and I don't see how HPVM could reconcile the two hardware pathes ...

If I had to do that, I would first unattach the tape drive from the VM on the source host, then migrate the VM to the second host and finally attach the tape drive from the second host to the VM.

HTH

Eric