Booting in maint. mode

[Abhijeet_3]

Hi,

I am uncertain about what is the exact difference between LVM maint. mode and Single user maint. mode.

Does Vg00 activated during this boot mode ?

What is the role of /stand/rootconf during this boot mode ?

Thanks

Abhijeet

[Arunvijai_4]

Hi Abhijeet,

Maintenance mode is intended only to enable you to rebuild the LVM data in the LIF area of boot disk after it has been damaged. It ignores the LVM data (which is in the LIF file "LABEL" ). There are two cases. Either the area after the boot area is the root filesystem or it is the /stand filesystem. In either case it must be contiguous and it must be an hfs filesystem so the boot program hpux can find the kernel. In maintenance mode, it is assumed to start after the boot area and consume the rest of the disk. But if it is /stand, a file called /stand/rootconf is read (by the kernel) and this is used to find the start of the root filesystem which is also assumed to extend to the end of the disk. This leaves them overlapping each other as well as any other logical volumes.

The result is that the kernel is running and root is mounted with nothing else. At this point you are supposed to rebuild the LVM info in the boot area. This typically involves using mkboot, vgcfgrestore, and lvlnboot. It is crucial that the disk not be synced at all. Either "reboot -n" or cycle power to exit maintenance mode.

Activating the root volume group is explicitly prohibited...doing so may corrupt it.

The kernel knew that oldroot on /dev/root was a mount point but it didn't know that oldroot on /dev/vg00/lvol3 was a mount point. That why you saw a difference.

http://www.unix.com/archive/index.php/t-4721.html

-Arun

[Robert-Jan Goossens]

Hi,

Check this doc.

Title: When do I use the different types of alternate boot methods ?
Document ID: KBRC00008690

http://www5.itrc.hp.com/service/cki/docDisplay.do?docLocale=en_US&docId=200000079989997

Regards,
Robert-Jan

[Steven E. Protter]

Shalom,

On a practical basis, I was doing LVM work in single user mode for a year before I went to an HP class and learned there was LVM maintenance mode.

Its possible to do the LVM work in single user and non-lvm work in single user mode.

The environment makes it a little easier to use the modes as intended.

SEP

[Raj D.]

Does Vg00 activated during this boot mode ?

In single user you have to activate it and to mount the filesystems. And hope same for lvm mm.

Cheers,
Raj.

[Sivakumar TS]

Hi Abijith,

The vg00 is NOT activated during LVM main mode - booting.

Regards,

Siva.