What is the procedure to mirror the root disk?

[kunjuttan]

Hi all,
What is the procedure to mirror the root disk?

[Pete Randall · Accepted solution]

The steps to mirror your boot volume are (PA-RISC):

1. Create a physical volume with a boot reserved area
"pvcreate -B /dev/rdsk/c1t6d0"

2. Add the physical volume to the root VG
"vgextend /dev/vg00 /dev/dsk/c1t6d0"

3. Use mkboot to place the boot utilities in the boot area and add the AUTO file
"mkboot /dev/rdsk/c1t6d0"
"mkboot -a "hpux -lq" /dev/rdsk/c1t6d0"

4. Use mkboot to update the AUTO file on the primary boot disk
"mkboot -a "hpux -lq" /dev/rdsk/c0t6d0"

5. Use lvlnboot to identify the root, boot, primary swap and dump lvols
"lvlnboot -r /dev/vg00/lvol3 /dev/vg00" (lvol4 if you have secondary swap in lv
ol3)
"lvlnboot -b /dev/vg00/lvol1"
"lvlnboot -s /dev/vg00/lvol2 /dev/vg00"
"lvlnboot -d /dev/vg00/lvol2 /dev/vg00"
"lvlnboot -v"
6. Mirror the stand, root and swap logical volumes in order
"lvextend -m 1 /dev/vg00/lvol1 /dev/dsk/c1t6d0"
"lvextend -m 1 /dev/vg00/lvol2 /dev/dsk/c1t6d0"
"lvextend -m 1 /dev/vg00/lvol3 /dev/dsk/c1t6d0"

7. Then mirror the rest of your root logical volumes
"lvextend -m 1 /dev/vg00/lvol4 /dev/dsk/c1t6d0"
etc.

8. Modify your alternate boot path
"setboot -a 8/8.6.0 # use the path of your new boot disk"

9. Edit /stand/bootconf and add your new mirrored boot disk.

That's all there is to it. You may notice that I left out the
lvlnboot -R command. That is because it is not
necessary - see the man page:

"This command should be run in recovery mode (-R)
whenever the configuration of the root volume group is
affected by one of the following commands: lvextend,
lvmerge, lvreduce, lvsplit, pvmove, lvremove, vgextend,
or vgreduce (see lvextend(1M), lvmerge(1M), lvreduce(1M),lvsplit(1M), pvmove(1M), lvremove(1M), vgextend(1M), and
vgreduce(1M)). Starting with HP-UX Release 10.0, this is
done automatically."


For Itanium architecture, follow this guide:
http://docs.hp.com/en/B2355-90950/ch06s02.html#cchgjafa

And, for 11.31, follow this:
http://docs.hp.com/en/B2355-90950/ch06s02.html#mrflv

[Torsten.]

You already have the link



http://docs.hp.com/en/5991-1236/When_Good_Disks_Go_Bad_WP.pdf



Not only save it, read it!



See appendix!

[kunjuttan]

Sorry Sir,
I am a mewbie to HP-UX.Wht I understood from the first part of the above doc is the following.Pls tell me if I am write or wrong.

Check the /var/adm/syslog/syslog.log file for errors.Errors will be like
â SCSI: Request Timeout -- lbolt: 329741615, dev: 1f0220000â =>Here 1f02200000 shows the device number.
Then
#ll /dev/*dsk | grep 022000
This will give you the respective device (ie c0t5do) which is failed.
#ioscan -fnC disk|grep NO -> look for not claimes Hard disk
You can do two more steps to confirm ie
#pvdisplay /dev/dsk/c0t5d0 =>In the output if the PV status shows unavailable then that PV is having some problems.
#diskinfo /dev/rdsk/c0t5d0 =>In the output if the disk size shows 0KB ,then also you can confirm that the disk is having some problem.

From the above steps you can confirm that the disk (c0t5d0) is having some problem.Now you want to check the specified disk is a part of rootv or not?for this you have to do,
lvlnboot â v =>This command will list all those PVs which are in rootvg.
Next to remove the mirror copy you have to use the command,
# lvreduce -m 0 -A n /dev/vg00/lvol1 /dev/dsk/c0t5d0 => The option â A n is used to prevent lvreduce command from performing an automatic vgcfgbackup operation, which might hang while accessing a defective disk.

#vgreduce /dev/vg00 /dev/dsk/cot5do

replace the faulty disk

#pvcreate

#vgextend /dev/vgxx

mirror back all the logical volumes

#lvextend -1 /dev/vgxx/lvolxx /dev/dsk/cxtxdx

[Hakki Aydin Ucar]

Hi,

you can also use this link:
http://pagesperso-orange.fr/hvelasco.admin/LVM%20HP-UX/root.htm#mirror_root

[Torsten.]

Sort your threads!


The question is about disk mirror, isn't it?



Please continue your failed disk thread.

[kunjuttan]

Sir,
can you please confirm what I put above is write or wrong?