Error mounting RPi root filesystem

Pheonix

@SGaist is it necessary for me to enter in root mode as i get this : only root can do that

SGaist

Hi and welcome to devnet,

Usually yes, it's needed to mount something. Unless there's an fstab entry that allows user to mount a certain mount point.

Pheonix

@SGaist while mounting image using this command :-mount -v -o offset=62914560 -t ext4 /home/iamsps/opt/rasberry.img/mnt/rasp-pi-rootfs

i am getting this

mount: wrong fs type, bad option, bad superblock on /dev/loop0,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so[link text](```

SGaist

I've moved your questions to it's own thread since they weren't related to the other thread directly.

Are you sure that your image uses ext4 as its root file system ?

Pheonix

@SGaist hi,

well sir i am not sure about that: but when i tried following command :-----
mount -v -o offset=62914560 -t auto /home/iamsps/opt/2015-11-21-raspbian-jessie.img /mnt/rasp-pi-rootfs

i get the following result:-

mount: enabling autoclear loopdev flag
mount: going to use the loop device /dev/loop0
mount: you didn't specify a filesystem type for /dev/loop0
I will try all types mentioned in /etc/filesystems or /proc/filesystems
Trying ext3
Trying ext2
Trying ext4
Trying vfat
Trying fuseblk
mount: you must specify the filesystem type
root@pheonix:/home/iamsps/opt#
**

SGaist

You should check with your running RPi, you'll be able to see which FS is used. Otherwise you can also use sshfs to mount the RPi's root filesystem but that requires to have the Pi running as well.

Pheonix

hi, @SGaist
i check the file system using command cat /etc/fstab on pi2 terminal it is ext4.

still whwn i use this command :- **mount -v -o offset=62914560 -t ext4 /home/iamsps/opt/2015-11-21-raspbian-jessie.img/mnt/rasp-pi-rootfs
**
*************i get the same error :-
mount: enabling autoclear loopdev flag
mount: going to use the loop device /dev/loop3
mount: wrong fs type, bad option, bad superblock on /dev/loop3,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so

what me be the possible causes of this and what i should do to solve this problem???????

Pheonix

hi @SGaist ,

when i run this command on my system :-
**dmesg | tail **

it shows:

JBD2: Error -5 detected when updating journal superblock for sdb2-8.
[87079.359285] Aborting journal on device sdb2-8.
[87079.359288] JBD2: Error -5 detected when updating journal superblock for sdb2-8.
[87079.359301] EXT4-fs error (device sdb2): ext4_put_super:788: Couldn't clean up the journal
[87079.359304] EXT4-fs (sdb2): Remounting filesystem read-only
[87079.359306] EXT4-fs (sdb2): previous I/O error to superblock detected
[87079.373998] sdb: detected capacity change from 31439454208 to 0
[87081.501477] usb 1-7: USB disconnect, device number 4
[89600.380314] EXT4-fs (loop3): VFS: Can't find ext4 filesystem

i am not sure i think this is causing error ?????

Pheonix

first check the starting point of image using fdisk -l raspberry.img

you will get:

****iamsps@pheonix:~/opt$ fdisk -l raspberry.img
**
Disk raspberry.img: 4127 MB, 4127195136 bytes
255 heads, 63 sectors/track, 501 cylinders, total 8060928 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x3e7fd08e

    **Device Boot      Start         End      Blocks   Id  System

raspberry.img1 8192 131071 61440 c W95 FAT32 (LBA)
raspberry.img2 131072 8060927 3964928 83 Linux**
**

now set the offset value: 512*131072= 67108864 and use command:

mount -v -o offset=67108864 -t ext4 /home/iamsps/opt/raspberry.img/mnt/rasp-pi-rootfs.

Pheonix

@SGaist

thanks sir for help.