You can clone a computer by copying all its files to another. There are some things you need to be aware of, that is what this topic is about.
- You have two computers and want one to act like the other
- You do Booting from USB and want to clone your USB disk
- You want to backup regularly
- You want to enhance your computer park
Which program should you use to clone
- cp -pr: Will not work because it does not handle devices and links correctly.
- tar: Can be used to copy files, can handle devices, links and hidden files correctly.
- rsync -avz: Should do the same as tar, it should only copy the files that differ. However, it has not yet been tested.
- dd: Used to take byte after byte and copy it. So it does not allow to change the size of partition and does not allow to use different file systems.
Cloning a USB disk
To clone a USB disk
- have your target disk deleted
- have your target disk bootable (see Booting_from_USB)
- have your target disk mounted (I assume under /mnt/sdb1)
- have your system booted from your source disk
- use tar to copy the files over
The above command excludes some directories from the copy: /proc and /sys that store the kernel's state, /tmp that is for temporary files and /media and /mnt that are for mounted filesystems.
Cloning between computers
Clone your computer like this:
- Have your source and target computer in one network.
- Use tar to transmit the files. This tutorial assumes your target's hostname is target, and you are working on the source computer:
with the parameter l you only tar the local filesystem and do not need to care about mounts, /proc and /sys. Maybe your computers have different hardware, e.g. network cards or disk controllers. Then you should leave the /boot directory on your target computer untouched - obviously, you cannot apply a kernel then. In this case, you can use the following transmission command:
cd / tar -cv -f- $(ls -1 | grep -Ev "proc|sys|tmp|media|mnt|boot") | ssh root@target "(cd /; tar -xv)"
The above command excludes some directories from the transmission: /boot that contains the kernel and initrd, /proc and /sys that store the kernel's state, /tmp that is for temporary files and /media and /mnt that are for mounted filesystems.