topic Re: mirror boot disk in Operating System - HP-UX

mirror boot disk

Ragni Singh — Fri, 15 Mar 2002 15:15:41 GMT

Hello,

How does one mirror a boot disk on a K-class server?. Any help will be greatly appreciated. Points will also be given.

Re: mirror boot disk

S.K. Chan — Fri, 15 Mar 2002 15:20:35 GMT

This is the process I used .. (you got to have Mirror/UX installed)

Mirroring Process
-----------------
o Assuming c1t2d0 is primary disk and c2t2d0 is the disk to be mirrored.
o Assuming (lvol1=/stand;lvol2=primary swap;lvol3=2ndary swap;lvol4=/;lvol5=/opt)

# swlist -l bundle| grep -i mirror
=> Make sure you have MirrorUX installed
# pvcreate -f -B /dev/rdsk/c2t2d0
# mkboot -l /dev/rdsk/c2t2d0
=> Create boot track (place boot utilities in boot area), -l means treat device as LVM disk.
# mkboot -a "hpux -lq" /dev/rdsk/c2t2d0
=> Add AUTO file in boot LIF area, "lq" option is to bypass quorum check.
=> Repeat for primary disk (c1t2d0) as well.
# lifcp /dev/rdsk/c2t2d0:AUTO -
=> Check content of AUTO file. Repeat for primary disk (c1t2d0).
# vgextend /dev/vg00 /dev/dsk/c2t2d0
=> Adding disk to root VG.
# pvdisplay -v /dev/dsk/c2t2d0
=> Note of the order of LVs (assuming it's lvol1,lvol2,lvol3,lvol4 & lvol5)
# lvextend -m 1 /dev/vg00/lvol1 /dev/dsk/c2t2d0
=> Repeat for lvol2->lvol5
# lvlnboot -r /dev/vg00/lvol4 /dev/vg00
# lvlnboot -b /dev/vg00/lvol1 /dev/vg00
# lvlnboot -s /dev/vg00/lvol2 /dev/vg00
# lvlnboot -d /dev/vg00/lvol2 /dev/vg00
=> Update BDRA (root, boot, swap and dump)
# lvlnboot -v
=> Check to make sure both disks are listed for root, boot and swap definition.
# setboot
=> Display boot path.
# setboot -a 0/0/2/0.2.0
=> Change alternate boot path to mirrored disk.
# shutdown -r -y 0
=> Interrupt upon bootup and select alt path to boot from in order to test.

Installing ODE (Offline Diagnostics)
------------------------------------
# ll /usr/sbin/diag/lif/updatediaglif
=> Make sure the file exist.
# lifls -l /dev/rdsk/c2t2d0
=> List content of LIF dir (should have ISL,AUTO,HPUX,PAD,LABEL).
# mkboot -b /usr/sbin/diag/lif/updatediaglif -p ISL -p AUTO -p HPUX -p PAD -p LABEL /dev/rdsk/c2t2d0
=> Install ODE LIF files while "protecting" the existing LIF files.
=> Use updatediaglif2 for 11.0 64-bit.
# lifls -l /dev/rdsk/c2t2d0
=> Should now see the additional LIF files.

Re: mirror boot disk

Helen French — Fri, 15 Mar 2002 15:22:08 GMT

Hi Sanman,

Check this document for all instructions:

http://us-support.external.hp.com/cki/bin/doc.pl/sid=4a4e396406a9acb208/screen=ckiDisplayDocument?docId=200000055534397

HTH,
Shiju

Re: mirror boot disk

S.K. Chan — Fri, 15 Mar 2002 15:23:20 GMT

I thought I throw in this as well .. this is optional.

Optional Step
-------------
o Changing the swap LV Consistency Recovery Policy

# lvdisplay /dev/vg00/lvol2
=> Check existing mirror consistency recovery policy for swap.
=> The default policy (ie MWC) requires additional IO overhead with every disk write. For best performance change it to "NONE" since there is no need to recover swap space after crash.
=> Procedure must be perform in LVM maintenance mode.
ISL > hpux -lm
=> Boot in LVM maintenance mode.
# vgchange -a y vg00
# lvchange -M n -c n /dev/vg00/lvol2
# reboot

Re: mirror boot disk

David Burgess — Fri, 15 Mar 2002 18:57:14 GMT

One thing to watch out for is that after you've been in lvm maintenance mode you can end up with a bdf showing roots filesystem as /dev/root :-

Filesystem kbytes used avail %used Mounted on
/dev/root 102400 28552 69240 29% /

This can cause problems with things like make_recovery as it calls save_config which relies on the information held in /etc/mnttab.

To get round this mv /etc/mnttab /etc/mnttab.old
Run the mount command to recreate the /etc/mnttab file.

Now the bdf shows the root filesystem correctly :-

Filesystem kbytes used avail %used Mounted on
/dev/vg00/lvol3 102400 28552 69240 29% /