alternate boot disk

[vlz]

Hi,
I have Solaris OS with Veritas volume manager.
My system boot disk was encupsulated to Veritas.
I'd like to have an alternate boot disk.
I need to backup system disk to it's alternate disk once a week.
If somebody has experience with this issue?
Thanks in advance
Vadim

 

[julianbarnett]

Suggest you have a mirror disk and alternative boot disk for best resilience.

Check out

http://www.sun.com/solutions/blueprints/0800/vxvmref.pdf

You will need another disk preferably on a different controller as large, or larger than your existing root disk paritions.

If disk has been added in-flight without rebooting.

'devfsadm -c disks'
'vxdctl enable'
'vxdisk list' - should show new disk

'/etc/vx/bin/vxdisksetup -i cNtNdN' - init new disk
'vxdg -g rootdg adddisk altboot=cNtNdN' - add to rootdg
'vxedit set nconfigall nlog=all rootdg' - keep VxVM config on all rootdg disks

'/etc/vx/bin/vxrootmir altboot' - mirror root partition
'vxassist -g rootg mirror swapvol altboot' - add swap
.. add any other (/opt, /var) from your root disk as above
'/etc/vx/bin/vxbootsetup altboot' - make it bootable

using eeprom command add altboot devalias to nvramrc and set use-nvramrc? to true

'vxprint | grep altboot' - note subdisk and plex names
'vxplex -o rm dis rootvol-0? swapvol-0?' - remove plexes
'vxedit set reserve=on altboot' - prevent VxVM from using

fsck all the partitions since they will be dirty
mount -Fufs /devv/dsk/cNtNdNs0 /mnt
create a file in /mnt indicating when copy was taken
edit /mnt/vfstab with new device names cNtNdNs0,1..
edit /mnt/etc/system, delete rootdev references to prevent VxvM trying to start on contingency disk boot

Test boot on contingency disk 'ok> boot altboot' check root is mounted as a standard not a VxVm device.

Have a look at using the Veritas persistent Data Change Object combined with snapshotting to enable a really quick resynchronisation.

JB

 

[Annihilannic]

FYI, Veritas can perform all of the mirroring steps, including vxbootsetup, in one go using vxmirror rootdisk rootmirror. Annihilannic.

 

[vlz]

Hi Julian,
Thanks for response.
As I understand the alternate disk
will be a maintenance boot disk without Veritas.
I.e. after booting from it I'll need to encapsulate it
and reboot the server.
Is it possible to have encapsulated alternate boot disk
and boot from it like from system boot disk?

 

[Annihilannic]

If you follow Julian's steps the second boot disk will be an exact copy of the first one. It will already be encapsulated, and you should be able to boot from it just like the first one. Annihilannic.

 

[vlz]

But Julian wrote:
Test boot on contingency disk 'ok> boot altboot' check root is mounted as a standard not a VxVm device.

 

[julianbarnett]

Second disk will be a point in time mirror of the first - not encapsulated since there was no data on it to begin with. Having mirrored the disk, we detach the plexes and remove them from Veritas. Edits made to /etc/system (remove rootvol from vxio and from rootvol) and /etc/vfstab to mount /dev/dsk devices for root disk mean it is not under Veritas control, BUT Veritas will be started. This means you can stil maintain your Veritas disks, make changes to the Veritas boot disk in the event that for some reason you cannot boot from one of the Veritas mirrors.

The Sun Blueprint link above describes this all far better than I have under the Clone Disks section and includes a script to do it all for you. The article also contains some suggestions for creating unencapsulated mirrored root environments to make maintenance of your Veritas disks easier as well. If you are really interested the Blueprints book 'Boot Disk Management' is a worthwhile investment although it dows cover a lot of the same ground as the PDF file.

JB