Booting system with one mirror disk

[Alfonso Gonzalez]

Is it posible to boot a system with only one of the mirrored disk inserted?

I tried to do it in a L2000 system with HP-UX 11.0 but I get an error during the boot of the system.

All logical volumes are mirrored on each disk, and both disk are bootable.

[Thierry Poels_1]

hi,

sure! ain't that the idea of mirroring ;-)

If you have a small number of disks in your VG00, and removed 1 or more disks, it might be possible you didn't meet the VG quorum (>50% of disks required to activate).
If that's the case:
- interrupt boot
- boot from mirror
- interact with ISL
- hpux -lq (=low quorum)

To avoid this problem the bootstring for the mirrored disk should contain "hpux -lq".

good luck,
Thierry

[Clemens van Everdingen · Accepted solution]

Hi,

During creating of second boot disk:
Did you use:

mkboot -a "hpux -lq (;0)/stand/vmunix" /dev/rdsk/cXtXdX

This to activate low quorum on both disks.

If not you can do it now.

Then you will be able to boot from one disk if the other one is defect or taken out !

C.

[S.K. Chan]

Yes, you can boot from any of the 2 bootable disks that you mirrored. What error did you get ? Did you interrupt the bootup and manually boot from the correct path that points to the disk ?

[S.K. Chan]

Yeah what Thierry & Clemens said makes sense, the quorum check. Basically if one or one more than half of your disks are not accessible during VG activation, our VG will not activate. So if you got 2 disks in your vg00 and did not set the quorum escape string in the AUTO LIF file, if one of the disks is not accessible, it will not bot up.

[Thierry Poels_1]

hmmmm, just to play sure, not to offend:

you DID make the mirrored copy bootable?? (pvcreate -B, mkboot, ...) Only mirroring all VG00 logical volumes is not sufficient.

regards,
Thierry.

[Trond Haugen]

Also did you mirror the first volumes in sequence? /stand MUST be the first on the disk as vmunix is loaded without LVM.
What was the error you got and when in the boot process?

Regards,
Trond