lvlnboot -v displays nothing for root,boot;swap

[Gerald_2]

Accidentally executed command: dd if=/stand/vmunix of=/dev/rds/k/cxtxdx bs=2048
on raw root disk. What is the best way to recover, if any, the root, boot; swap area
on root disk. If there is no way to recover, then what is the best way to create new "root"
disk, and copy data from damaged root disk
to new root disk drive. Need specifics.

Thank you.

gcp

[Sanjay_6]

Hi Gerald,

Looks to me that your root disk is gone if that cxtcdx you are referring is your root disk. Are you still able to work with that. If your root disk is gone and you don't have a mirror copy, you have to reinstall the OS. I doubt you'll be able to recover anything from the disk cxtxdx. Anyway maybe someone can help. Keep your fingers crossed.

Thanks

[Tom Danzig]

I think your in trouble. You overwrote the first 10-16MB of data on your root disk (depending on the size of your kernel) which contains the LIF area. Hope you have a make_recovery tape handy. If not, restore the OS from the installation media and restore from any other soure of root disk backup that you have.

[James R. Ferguson]

Hi Gerald:

I hope you have an Ignite make_tape_recovery tape from which to recover. Otherwise, you're looking at a cold-install.

...JRF...

[Shahul]

Hi

If the specified device file is the device file of root HDD, then U will have to go for an OS installation even though it was accidental. If U have mirror copy of root HDD, then U can boot thru that.

Best of luck

Shahul

[Shahul]

Hi

If the specified device file is the device file of root HDD, then U will have to go for an OS installation even though it was accidental. If U have mirror copy of root HDD, then U can boot thru that.

Best of luck

Shahul

[Sridhar Bhaskarla]

Gerald,

You might have corrupted your boot area. So, do not reboot the box. Take a make_recovery of the system and then re-install. If you already rebooted the system, then you don't have any other option except to reboot.

But before rebooting, I would try to refresh the boot disk if at all it works by starting with mkboot etc.,. Follow the usual process and see if it works. I have very minor hopes on it though.

-Sri

[Wodisch]

Hello Gerald,

first: how big is that kernel you copied?
is it your root- and boot-vg?
is it the only disk in there?

second: DO NOT REBOOT NOW!

third: run the following commands to re-create the
overwritten areas (it might not be possible, depending
on the amount of space you have overwritten):

1) vgcfgrestore -n /dev/vg00 /dev/rdsk/cxtydz
2) mkboot /dev/rdsk/cxtydz
3) lvlnboot -b /dev/vg00/lvol1 # is this your /stand?
4) lvlnboot -r /dev/vg00/lvol3 # is this your root-fs?
5) lvlnboot -s /dev/vg00/lvol2 # is this your swap space?
6) lvlnboot -d /dev/vg00/lvol2 # is this your dump area?

well, if you got that far, perhaps you are restored
- BUT DO NOT TRUST THAT RIGHT NOW!
First create a bootable copy of your whole system on
tape: get and install "Ignite/UX" if it is not there, already.
Do it: "make_tape_recovery -AvI"

Test your backup tape:
mt -t /dev/rmt/0mn fsf 1 # fast forward over bootcode
tar tvf /dev/rmt/0m # do get the list of files?

only now you may try to reboot...

Good luck!!!
Wodisch