boot from mirrored vg00

[james mcintyre_1]

i have mirrored vg00. now would like to test the mirror. anyone have a process to split the lvol's and reboot from the mirror ?

thanks....jim mc.....

[erics_1]

James,

Why split the mirror when you could just boot from your alt. boot disk? Interrupt the boot sequence on the system and boot from the alternate (mirror) disk. Do not choose to interact with ISL. The system should come up fine on your mirror disk.

Regards,
Eric

[Patrick Wallek]

No real need to split the mirrors or anything.

Just reboot the system, "press any key within 10 seconds" to interrupt the boot process and do a 'bo alt' at the prompt, assuming that the mirror boot disk you want to test is your alternate boot disk. If it's not do a 'sea ipl' and choose the path of the disk you want to boot from.

This is the best / easiest way to check without incurring any unnecessary work.

If your boot disks are hot swappable, you could always just pull one of the disks and see how your machine behaves.

[Uday_S_Ankolekar]

As all said no need to split the mirror to test this out. Or if you can not boot the server now, try typing lvlnboot -v command. You should be seeing two boot disks with their respective path. This way you are sure that there is a mirrored boot disk is configured.

-USA..

[Christopher McCray_1]

Hello,

You don't need to split the lvols. Just reboot, interrupt the boot process and type boot alt and say no to interact with ISL.

Hope this helps

Chris

[Jeff Schussele]

Hi Jim,

No need to baysit the boot process.
Just run
setboot
and not the HW addresses of the current primary & alternate bootpaths.
Then run
setboot -p org_alt_path -a org_pri_path
effectively switching the primary & alternate paths.
Then just
shutdown -r -y now
and you'll test booting the alternate.
Save yourself a trip to the datacenter.

HTH,
Jeff

[Eugeny Brychkov]

Want to crash your system? No problems!
If you have one of the disks as hot swappable simpy pull it out.... and see how system behaves. Then try to reboot...
BUT before doing this make recovery tape and read how to get mirror working back on vg00
Eugeny

[Lars-Olof Fermvall]

You may want to make sure that everything is set up for root disk mirroring. I found this entry in the forum very helpful when I did it: http://forums.itrc.hp.com/cm/QuestionAnswer/1,,0xfe24543254bfd611abdb0090277a778c,00.html

[Ionut Grigorescu_2]

just do
#ioscan -funC disk
write down the hardware path of the mirror disk, then reboot, interrupt the boot sequence within 10 sec, then type sea
You shall see a list with the possible boot paths, something like:
P1 8/8.6
.
.
.etc.
See what is the HW path of your mirror and type
bo Px
Do not interract with ISL
Good luck!

[KapilRaj]

Is it a hot swap disk. then,

Bring down the server & press a key in 10 seconds ........

bo alt
Interact IPL: "Y"
hpux -lq (is used 'cause vg00 will not get activated as there is no quorum.....)

System should come up as usual & it should show all the FS

kaps

[KapilRaj]

sorry add one more comment .....

bring down the server

take out the disk & then

bo alt

kaps

[james mcintyre_1]

If I just wanted to test the mirror, yes I would just reboot from the mirror. My desire is to take the test to the next level. Split the mirrors and reboot from either disk. Given that I can install patches or test my ignite tape backup restore. if the world turns to sh.., I can reboot the untouched system and go home for a guiness. Also, I do not have an extra drive laying around.

thanks to all you have replied........

[erics_1]

Jim,

In that case, there's a couple of documents on TKB that I think you'll find useful. The first one documents how to split the mirrors while the second shows how to boot from it. Hope it helps!

TKB Docs:
LVMKBRC00005100
rcfaxlvm007

Regards,
Eric

[james mcintyre_1]

erik:

i have searched tkb and have not been able to locate the doc's you mentioned below. what am i doing wrong ?

jim mc....

[Sridhar Bhaskarla]

Jim,

To really test if the mirror is working or not, pull out the primary disk. If you can do it online (with RP* series), then the system should continue functioning with few errors in syslog. If not, you should be able to boot with one disk with few complaints. You will need to make sure that the autostring is set to "hpux -lq". Once your testing is done, you can do a vgsync to sync the mirrors.

-Sri

[Patrick Wallek]

I just searched the TKB and found the documents without a problem.

When you search, you must change the search method you use. Just to the left of the input box, there is a drop down list with 2 choices. The first (and default) is "Search by keyword", the 2nd choice, and the one you want when looking for a specific document ID is "Search by Doc. ID". Choose that one, then put the document ID in the search field and it should come up.

[James R. Ferguson]

Hi James:

To access the TKB (Technical Knowledge Base) make sure you are logged into the ITRC. Also, be sure to toggle "Search by Doc. Id.". The default is "Search by Keyword". This dropdown is to the immediate left of the Search String box.

Regards!

...JRF...

[Steven E. Protter]

Before you test, try this...

[1042#] lvlnboot -v
Boot Definitions for Volume Group /dev/vg00:
Physical Volumes belonging in Root Volume Group:
/dev/dsk/c0t5d0 (8/4.5.0) -- Boot Disk
/dev/dsk/c0t8d0 (8/4.8.0)
/dev/dsk/c0t9d0 (8/4.9.0)
/dev/dsk/c1t0d0 (8/12.0.0)
/dev/dsk/c1t1d0 (8/12.1.0)
/dev/dsk/c1t2d0 (8/12.2.0)
/dev/dsk/c1t8d0 (8/12.8.0) -- Boot Disk
/dev/dsk/c0t11d0 (8/4.11.0)
/dev/dsk/c1t5d0 (8/12.5.0)
/dev/dsk/c1t4d0 (8/12.4.0)
/dev/dsk/c1t6d0 (8/12.6.0)
/dev/dsk/c0t10d0 (8/4.10.0)
Boot: lvol1 on: /dev/dsk/c0t5d0
/dev/dsk/c1t8d0
Root: lvol3 on: /dev/dsk/c0t5d0
/dev/dsk/c1t8d0
Swap: lvol2 on: /dev/dsk/c0t5d0
/dev/dsk/c1t8d0
Dump: lvol2 on: /dev/dsk/c0t5d0, 0


If you don't see two boot disk's don't bother with the test.

Here are exerpts from the process of creating a dual boot disk.

pvcreate -f -B /dev/rdsk/c2t2d0

# Add the mirrored disk back to the group.
vgextend /dev/vg00 /dev/dsk/c2t2d0

# Copy the boot area to the disk:
mkboot -l /dev/rdsk/c2t2d0
mkboot -a 'hpux -lq' /dev/rdsk/c2t2d0
# Allocate the mirrors. Mirrors must be allocated for all
# logical volumes that were previously mirrored. This
# example illustrates Primary Swap and Root. You can
# add others as needed.
lvextend -m 1 /dev/vg00/lvol1 /dev/dsk/c2t2d0
lvextend -m 1 /dev/vg00/lvol2 /dev/dsk/c2t2d0
lvextend -m 1 /dev/vg00/lvol3 /dev/dsk/c2t2d0
lvextend -m 1 /dev/vg00/lvol4 /dev/dsk/c2t2d0
lvextend -m 1 /dev/vg00/lvol5 /dev/dsk/c2t2d0
lvextend -m 1 /dev/vg00/lvol6 /dev/dsk/c2t2d0
lvextend -m 1 /dev/vg00/lvol7 /dev/dsk/c2t2d0
lvextend -m 1 /dev/vg00/lvol8 /dev/dsk/c2t2d0
# Update the BDRA and LABEL file
lvlnboot -R

This is from an ignite script but it works as a standalone script or from the command line.

Steve