lunes, 25 de febrero de 2013

Arranque de emergencia al editar fstab

Arranque de emergencia al editar fstab

Hay veces que al modificar el fstab no arranca bien el sistema y nos vemos obligados a recurrir a diversos métodos para poder arreglarlo. Yo probé estos y con la segunda lo pude arreglar bien. Todo se debía a que configure las unidades para montarlas con el UUID pero al cambiarlas de formato de EXT4 a XFS también cambia el UUID y se quedaba atascado al arrancar.

Bypassing Bad fstab Failure While Booting Linux


If /etc/fstab file is created with errors or the hardware configuration changes such as adding hard disks, Linux will boot into failure state. We can bypass the fstab failure by adding booting parameters to Linux. We can do this in two methods:


Method 1: Boot to single user mode

When booting into single user mode, Linux will not mount anything. Then we can remount the / to some directory in read/write mode and then edit the /etc/fstab.

1. Boot Linux into single user mode

Press ESC in the grub menu and press ‘e’ to edit the grub entry. Add single to the kernel parameter like this:

kernel /vmlinuz-2.6.32.21-166.fc12.i686 ro root=/dev/mapper/VolGroup-LogVol00 vga=792 

Then press ‘b’ to boot Linux.

2. Remount / in read/write mode

# mount -n -o remount,rw /

3. Edit /etc/fstab

If the above method doesn’t work, the second method can be used:

Method 2: Add init=/bin/bash to kernel parameter

 

Add to kernel parameter. Linux will boot and we will get a bash prompt. The / is mounted in read/write mode. We can then edit /etc/fstab file and reboot.

rw init=/bin/bash 

PD: A mi me funciono el método 2.