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I wanted to make a backup of a RedHat server, it's a big old HP machine and it's running a fairly important piece of software. At the moment the HP machine backs up its data but not the OS and I wanted a quick way to get the server up and running again in case of hardware failure,
The machine uses 2 80GB SATA drives and not being that familiar with it (and not wanting to have the server off line for too long)I decided to boot to an Acronis disk, make an image of both disks onto a USB external drive and reboot back to RedHat afterwards, so that all went well, server is back up and running no with trouble.
Brought the USB drive back to the workshop ready to burn image to DVDs and store it.
Thought to myself hmmmm can I test the image to see if it is ok? so set up a machine with 2 80GB Sata drives and restored the image to them, however upon restarting the machine I get this:
Creating block devices
Ext2-fs unable to read super block
isofs_read_super:bread failed, dev=09:00, iso_blknum=16, block=32
Ext3-fs:unable to read super block
Kernal panic VFS unable to mount root fs on 90:00
Now I have looked around at lots of places on the net and one answer keeps coming up a lot, does the fact that these two machines have completely different hardware (motherboards, cpus etc) have something to do with why it will not boot?
Sorry if this is a completely noobish question but that's unfortunatly where I am with this
Any help appreciated
That could be a problem but those error messages may indicate that the hard drives are not in the same position on the SATA bus as the original drives. Everything in linux is configured around where those drives are located. You have to get the original /dev/sda drive into the sda sata connector on the new box and the original /dev/sdb drive to the sdb connector on the new box. Those error messages indicate that the system is looking for the root file system where it was told to but can't find it there. If you restored the sda image to sdb, you would get just those error messages.
You would also get those error messages if the sata controller in the new box was different than on the old box and there was no driver available for it in the initrd. In that case it wouldn't be able to find any drives and thus no root file system.
Thanks for the reply, on further testing it seems the drivers are the issue, I am happy because I now have a complete backup of the data...but I guess I need to figure out a way to get it back onto the server in the event of hardware failure.