Run fsck on root file system

UNIX for Beginners Q & A UNIX for Dummies Questions & Answers
1

If i run fsck on one filesystem and fsck need to repair some things then this partition must be unmounted

correct ?

So running fsck on root file system isn't possible within same OS ? correct ?

What is the best way to do that, live cd ?

BR,

Jurif

2

Or single user mode (init state 1)

The problem isn't that it's mounted; it's that you don't want any other process writing to the fs while fsck is running.

3

I don't think so

because if i boot to single user mode than root fs is mounted read only and therefore fixing on that partition isn't possible

from fsck_ffs(8)

4

Which is why you'd usually remount the file system as read/write

mount -o rw /
5

Your instinct is correct. Don't mess around and get tricky or you will live to regret it. Go simple and boot from knoppix.

And back up anything critical before you do any filesystem repair - even if it's on another volume or partition.

6

You boot into single-user mode from the Solaris install CD/DVD. Take your system to the OBP with

init 0

and put the CD/DVD into the drive. Then boot from the CD/DVD with

boot cdrom -s

Once you get the "#" prompt run fsck ON THE RAW PARTITION like this:

fsck /dev/rdsk/c0t0d0s0

This may modify the root partition so NEVER NEVER NEVER run fsck with the "-y" flag.

I speak from experience on this issue. :o