Broken fstab, unable to boot

[Feisst]

Hello

In the fstab, the entry for the /usr (mounted on /dev/vg00/lvol4) is not correct. Know we are not able to boot the machine.

How to repair the fstab ?
Or how to boot a rescue shell and mount a LVM ?

[Bill McNAMARA_1 · Accepted solution]

At the boot menu:

Main Menu : Command Menu > BO PRI

Interact with IPL > Y

ISL > hpux -is

you'll get a prompt and can edit, fstab...
with sed etc.. not that you'll not have /usr available

#


Later,
Bill

[Bill McNAMARA_1]

well afterall,
you can at the prompt:

vgchange -a vg00

mount /dev/vg00/lvol7 /usr
mount /dev/vg00/lvol8 /var

and procede to edit the fstab with vi.

Later,
Bill

[Stefan Farrelly]

Just boot the server in lvm maintenance mode (hpux -lq), activate vg00, mount lvol3 (/) onto a temporary mountpoint (eg. mkdir tmp_mnt) then cd /tmp_mnt/etc and take a look at /etc/fstab and try to rebuild it. You wont be able to use vi (need /usr) but you can use echo >> to rebuild it and then reboot.

[Pete Randall]

An idle question, Stefan. How can you look at fstab if you don't have /usr mounted? All the commands I can think of are in /usr: cat, more, even strings. I suppose you could null it out with echo and then use echo to build a basic, stripped down version but there don't seem to be many other choices.

Pete

[Stefan Farrelly]

Actually, the question didnt say /usr had a problem so after mounting lvol3 to a temporary mount you can also mount /usr (manually) then you can use vi !

If /usr was corrupt then you could use echo to rebuild the fstab file line by line (echo ... >>/etc/fstab)

[Robert Thorneycroft]

Pete you will find an extra copy of cat hidden under /sbin as well as the more usual location of /usr/bin.

Kind regards,

Robert Thorneycroft

[Pete Randall]

Cool - thanks, Robert!

Pete

[Bill McNAMARA_1]

if usr is corrupt and you cant mount it - so cant edit easily ..
you can use mount to mount what you can, then
mount -p > /etc/fstab

Later,
Bill

[Feisst]

Hi

Only the fstab was broken, /usr was ok. Machine is up again. Thanks for the help.