yes iam on the same distro
first i tried to edit /etc/fstab in single user mode
it denied doing coz of read only mode
Noh, you were trying to edit the running fstab locked by the liveCD, of course that's a big "no" as a rule.
then i tried to run mount -o remount,rw /
it give me the following error
warning : can't open /etc/fstab : No such file or directory
mount: can't find / in /etc/fstab or /etc/mtab
The running system locked it.
i am running these commands after running su -
Yes but the liveCD system is greater than you.
Your problem is simple, you only need to reconstitute a text file and put it into its proper place. Had you posted to us your 'fdisk -l' output we would have known enough what file system you run, an ext2, ext3, ext4 or raiser? and would have posted you the correct texts. Run --# fdisk -l first and find ascertain the partitions and edit the instructions below accordingly.
Here is what you need to do.
1. Boot the live CD.
2. Check the partition: root@livecd-# fsck -a /dev/sda3
3. Mount it rw:
root@livecd-# mkdir /mnt/mysda3
root@livecd-# mount -o rw /dev/sda3 /mnt/mysda3
(Now it's there waiting to get manipulated.)
4. Follow these series of terminal commands:
--# touch fstab
--# echo '/dev/sda3 / ext3 defaults 1 1' >> fstab
--# echo 'proc /proc procfs defaults 0 0' >> fstab
--# echo 'tmpfs /dev/shm tmpfs defaults 0 0' >> fstab
--# echo 'devpts /dev/pts devpts user,rw 0 0' >> fstab
--# echo '/dev/cdrom /media/cdrom iso9660 noauto,user,ro 0 0' >> fstab
--# chmod 766 fstab
--# cp ./fstab /mnt/mysda3/etc
(Take note of the spaces and single quotes (') and the pipe >>)
(Assuming that your /, /boot and /tmp dirs reside in the same partition, it's a go)
Now it's time to reboot into your hard drive root.
After logging back into the old system you must recover the original fstab from the trash and replace the one you temporarily made.
Hope this helps. Good luck.