Failed mirror in VM Host storage allocated to VM Guests

[N Ward]

The disk is part of a mirrored volume group on the VM Host. There are 4 disks in the mirror. There are 4 LVs in the VG and each is assigned out to a guest as a single lun and is the guests vg00.

[Torsten.]

I understand that the command like this one just fails on the host with device busy:

# sasmgr replace_tgt -D /dev/sasd0 -q old_dev=/dev/dsk/c1t4d0 -q new_tgt_hwpath=0/4/1/0.0.0.11.0

[N Ward]

Yes the sasmgr command that needs to be run first fails too with device busy.

[Torsten.]

So I would just forget the old device file, delete it from configuration and add the mirror to the new device file.

[N Ward]

HP have stated its a known problem and I need a later SerialSCSI to fix it. The only way is to reboot for now.

What I'm concerned about with the mirroring is the LVs within the VG on the VM Host are vg00s on the guests. Is a straightforward mirror good enough for the this or is something else needed considering potentially the guest will have to boot from the mirror in a failure scenario.

[Torsten.]

As long as the LVOLS on the host are there, the guest will be happy.

[N Ward]

ok, so from a VM point of view, no associated boot disk tasks are needed for the mirror?

[Torsten.]

Exactly.

The presented LVOL (from host view) remains the same, mirrored or not.

[N Ward]

ok thanks for that...

[SoorajCleris]

Hi N Ward,

As you have already removed the OLD device from VG and LV configuration (lvreduce and vgreduce), now you can use new device file to mirror the LVs.

Just extend the VG with new device file, and mirror the LVs again.

The VG/the VM Guests will not affect with this. They will runfine as they are mapped to the LVs which are still available and running.( As Torsten already mentioned.)

All you can get is avoiding a reboot.

Regards,
Sooraj