initrd

[Chakravarthi]

is there any way to check the contents of .initrd file??

[Slawomir Gora]

Hi,

I am not sure you are asking about /boot/initrd.gz file ?


on my system I can:
cd /tmp
cp /boot/initrd_2.6.11-mm1.gz
gzip -d initrd_2.6.11-mm1.gz
mount -o loop /tmp/initrd_2.6.11-mm1 /mnt/

replace you initrd file name with my initrd_2.6.11-mm1.gz

[Chakravarthi]

file what i'm taking about is xx.initrd

it is not a bz or tgz file

file returns it is data file

[Slawomir Gora]

Hi,
did you try this ?

mount -o loop xx.initrd /mnt/

[Gopi Sekar]

if it shows as data file then it is more likely that it is not having any filesystem in it, there is no point in trying to mount it in -oloop method.

I think the name initrd is given just to confuse you. Which application is creating file by this extension?

FYI: If the initrd contains the filesystem then when you put 'file ' then it should give something like 'Linux rev 1.0 ext2 filesystem data'

Hope this helps,
Gopi

[Chakravarthi]

when i try mounting using -o loop option it gives the following error message

mount: you must specify the filesystem type

[Gopi Sekar]

So it clearly means that you are trying to mount a file which is not having any file system in it, the name initrd is given just to confuse you.

Which application is using this type of file?

Regards,
Gopi

[Stuart Browne · Accepted solution]

Generally an 'initrd' image is compressed, even if it doesn't have a '.gz' extension.

To check, you can use the 'file' command:

file initrd-2.4.22-1.2199.5.legacy.nptl.img
initrd-2.4.22-1.2199.5.legacy.nptl.img: gzip compressed data, from Unix, max compression

(this is on my fedora-core-1 machine).

The instructions Slawomir were pretty close.

So, either rename it to .gz, then uncompress it, or do it in pipes:

gzip -cd < initrd.img > loop-mount.img
mount -oloop loop-mount /mnt

and away you go.

[Mark Kounalis]

The way initrd stores it's information has changed. It's stored in a cpio file now - so after you uncompress the file you need to do a cpio -t < <> to see the contents.