How to verify root disk mirroring is working?

[zhaogui]

Can anybody tell me how to verify that root disk mirroring is working? how can I boot up the system from mirrored disk?

Thanks,

[Michael Tully · Accepted solution]

Here is the information your looking for:

# lvlnboot -v
Boot Definitions for Volume Group /dev/vg00:
Physical Volumes belonging in Root Volume Group:
/dev/dsk/c0t6d0 (0/0/0/2/0.6.0) -- Boot Disk
/dev/dsk/c2t6d0 (0/0/0/3/0.6.0) -- Boot Disk
Boot: lvol1 on: /dev/dsk/c0t6d0
/dev/dsk/c2t6d0
Root: lvol3 on: /dev/dsk/c0t6d0
/dev/dsk/c2t6d0
Swap: lvol2 on: /dev/dsk/c0t6d0
/dev/dsk/c2t6d0
Dump: lvol2 on: /dev/dsk/c0t6d0, 0

The only to tell for sure is to actually boot off your secondary to disk to check whether it works. So when you boot follow this procedure from the manual.

http://docs.hp.com/cgi-bin/fsearch/framedisplay?top=/hpux/onlinedocs/5185-6558/5185-6558_top.html&con=/hpux/onlinedocs/5185-6558/00/00/4-con.html&toc=/hpux/onlinedocs/5185-6558/00/00/4-toc.html&searchterms=boot%7cfrom%7cmirror&queryid=20020715-185947

[Sridhar Bhaskarla]

1. Do a lvlnboot -v and make sure the mirror disk is showing up as boot disk in the output as well for root,boot and swap logical volumes.

2. Do lifls /dev/dsk/c?t?d? and make sure the lif files are listed out.

3. Do lifcp /dev/dsk/c?t?d?:AUTO - and see if it is giving out correct boot string.

4. Run setboot command and verify that the alternate path is correctly displayed.

5. Do an lvdisplay on all vg00 logical volumes and grep for 'stale' entries. You should not get any.

4. Shutdown the system. Stop at the boot admin. The following may change depending on your hardware type.

Type bo

Say No to primary boot.
Say Yes to alternate boot.
Say No to ISl interact.

The system should come up without any errors.

The above can also be done using setboot command. If you are using setboot command, make sure you specify correct paths for primary and secondary.

Perfect check will be to take out the primary disk and boot from the alternate disk with the above procedure.

-Sri

[Michael Tully]

Please be sure to assign points to people who assist you. They do so using their own free time and resources. Your record of 37 assignments to 291 responses is not good....

[zhaogui]

# lvlnboot -v
Boot Definitions for Volume Group /dev/vg00:
Physical Volumes belonging in Root Volume Group:
/dev/dsk/c1t2d0 (0/0/1/1.2.0) -- Boot Disk
/dev/dsk/c2t2d0 (0/0/2/0.2.0) -- Boot Disk
Boot: lvol1 on: /dev/dsk/c1t2d0
/dev/dsk/c2t2d0
Root: lvol3 on: /dev/dsk/c1t2d0
/dev/dsk/c2t2d0
Swap: lvol2 on: /dev/dsk/c1t2d0
/dev/dsk/c2t2d0
Dump: lvol2 on: /dev/dsk/c1t2d0, 0


So in my case, I should run
ISL>boot 0/0/2/0.2.0
Is that correct?

[Sridhar Bhaskarla]

Yes. The path is correct. Also verify it using "setboot" command without any options.

No. You should be interacting with the boot admin prompt(or BCH boot control handler) before going into ISL prompt. When the systems performs it's hardware tests, it will come to this stage and waits for 10 sec for manual interaction otherwise boots from the primary path automatically. You will need to press any key during this time.

-Sri

[Michael Tully]

No thats not correct. Follow this procedure

If the autoboot and autosearch flags are enabled, PDC will provide you with a 10 second delay in which to manually override the automatic boot process. Press any key during these 10 seconds.

PDC will ask you:

Boot from primary boot path (Y or N)?
Answer no
Boot from primary boot path (Y or N)? N

PDC will then ask you:

Boot from alternate boot path (Y or N)?

If the alternate boot path is the correct hardware path for the device that you want to boot from, enter Y. If, as in the is example, the alternate boot path is not the desired hardware path, answer N:

Boot from alternate boot path (Y or N)? N

You will then be prompted to enter a command:

Enter boot path, command, or ?> bo 0/0/2/0.2.0

Interact with IPL (Y or N)> no

System should start to boot

[T G Manikandan]

you can use setboot to set the alternate path to the mirrored disk.

Look for the man pages of setboot.


Thanks

[James R. Ferguson]

Hi:

You can also verify the boot disk after the fact with:

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

This will return something like:

boot_string:
boot_string: disc(10/0.6.0;0)/stand/vmunix

...which can be related to 'lvlnboot -v':

Boot Definitions for Volume Group /dev/vg00:
Physical Volumes belonging in Root Volume Group:
/dev/dsk/c0t6d0 (10/0.6.0) -- Boot Disk
/dev/dsk/c2t0d2 (10/8.0.2) -- Boot Disk
/dev/dsk/c5t1d2 (10/16/4.1.2) -- Boot Disk
...

Hence, the boot occured from /dev/dsk/c0t6d0.

Regards!

...JRF...

[harry d brown jr]

Is there a reason that you have such a POOR record of assigning points?

This member has assigned points to 41 of 297 responses to his/her questions.

Fix them by starting here:
http://forums.itrc.hp.com/cm/TopSolutions/1,,CA698738!1!questions,00.html

live free or die
harry

[Christopher Caldwell]

Use my favorite technique--the proverbial smoke test.

Pull one of the mirror drives (why don't you pull the primary). Shutdown the system. Reboot - if you got an "optimal" setup, the box will autoreboot w/o operator intervention.

Watch out for quorum problems and incorrectly configured boot paths.

If everything works, replace the drive and sync the mirrors.

[Yogeeraj_1]

Hi,

To make sure, you can remove one of your hot-swappable mirrored boot disk and try!

You will be dead sure then ;)

(I hope experts will agree with me. We did that test when we got our new servers)

Best Regards
Yogeeraj

[Chris Lonergan]

Hi

Yogeeraj is right and it's the only surefire way. If you boot off the mirror with the primary in place the OS will boot even with stale extents on the mirror.

NB you will need the low quorum option when booting.

i.e. hpux -lq

Regards

Chris