Mirror Boot Disk

[srinivasa rao vaddadi]

Hello All,
i'm trying to create mirror boot disk.
but please find the below error mesg.


# mknod /dev/vg01/group c 64 0x010000
# vgcreate /dev/vg01 /dev/dsk/c2t2d0
Increased the number of physical extents per physical volume to 8683.
vgcreate: Volume group "/dev/vg01" could not be created:
VGRA for the disk is too big for the specified parameters. Increase the
extent size or decrease max_PVs/max_LVs and try again.
#
so do i need to change any parameters.
And our maxvgs parameter is holding the value 10.

[James R. Ferguson · Accepted solution]

Hi:

The Volume Group Reserved Area (VGRA) is too big to fit into one physical disk extent.

You will need to recreate the volume group specifying a larger PE size, a smaller number of physical volumes, or a larger number of maximum physical extents.

These parameters are fixed at 'vgcreate'. See the man pages for more information.

I suggest a larger '-s pe_size' and/or a much larger '-e pe_max'. These have the most firect impact on the size of the VGRA.

Your kernel 'maxvgs' parameter does not come into play for this.

Regards!

...JRF...

[Devender Khatana]

Hi,

The disk size seems to be atleast 36Gb here. So you shall increase PE_Size parameter here to atleast 16MB. Use

#vgcreate -s 32 /dev/vg01 /dev/dsk/c2t2d0

maxvg will not effect this unless you have approached 10 vgs in your system which shall not be the case here.

HTH,
Devender

[James R. Ferguson]

Hi (again):

BTW, if you are trying to mirror the boot disk (vg00) you should follow this:

# pvcreate -B /dev/rdsk/cXtYdZ
# vgextend /dev/vg00 /dev/dsk/cXtYdZ
# mkboot /dev/rdsk/cXtYdZ
# mkboot -a "hpux -lq" /dev/rdsk/cXtYdZ
# for LV in 1 2 3 4 5 6 7 8
> do
> lvextend -m 1 /dev/vg00/lvol${LV} /dev/dsk/cXtYdZ
> done
# lvlnboot -v

# mkboot -a "hpux -lq" /dev/rdsk/cXtYdZ #...or original volume, too...
# setboot -a [alternate_path] #...for new mirror...
# lifcp /dev/rdsk/xCtYdZ:AUTO - #...copy to stdout for verification

Note that you must start with a 'pvcreate -B'. Note too, that you 'vgextend' instead of 'vgcreate' your mirror.

Regards!

...JRF...

[Devender Khatana]

Hi,

JRF is right. you should not be creating a new VG for mirroring root rather shall be doing a vgextend. If the disk used now is bigger than the existing disk in vg00 then these parameters above can not be changed and you might have problems in allocating the whole disk space.

HTH,
Devender

[srinivasa rao vaddadi]

Hello JRF,
Thanks for your kind support.
we have created mirror boot disk.

we have booted from the alternative disk.
But how can i know from which disk (pri/ alt ) i have booted from.

Do we have any cmds. to check from which disk i have booted.

once again thanks a lot.

Cheers :)

[Sยภเl Kย๓คг]

Hi,

Use setboot command to findout the pri/alt paths. This will display the physical hardware path. Check the followings

Krishna-/>lvlnboot -v vg00
Boot Definitions for Volume Group /dev/vg00:
Physical Volumes belonging in Root Volume Group:
/dev/dsk/c0t4d0 (0/0/1/1/0.4.0) -- Boot Disk
/dev/dsk/c16t6d0 (2/0/2/1/0.6.0) -- Boot Disk
Boot: lvol1 on: /dev/dsk/c0t4d0
/dev/dsk/c16t6d0
Root: lvol3 on: /dev/dsk/c0t4d0
/dev/dsk/c16t6d0
Swap: lvol2 on: /dev/dsk/c0t4d0
/dev/dsk/c16t6d0
Dump: lvol2 on: /dev/dsk/c0t4d0, 0
Dump: lvol9 on: /dev/dsk/c0t4d0, 1

Krishna-/>setboot
Primary bootpath : 0/0/1/1/0.4.0
Alternate bootpath : 2/0/11/1/0.0.0

Autoboot is ON (enabled)
Autosearch is ON (enabled)

Regards
Sunil

[vinod_25]

Hi Srini

The solution text and Parameter table is here in this useful link.

http://docs.hp.com/en/6054/Limits_wp.htm

Let us know if that didnot serve the purpose.

Vinod

[srinivasa rao vaddadi]

Thanks Krishna and vinod.
For ur cmds and document.

[James R. Ferguson]

Hi (again):

To see which disk you booted from, do:

# echo boot_string/S|adb /stand/vmunix /dev/mem

Regards!

...JRF...