Which tool to backup an ext4 partition?

I'm searching for a tool to backup a whole ext4 partition to an image. I tried the latest version of mondo, which is not working. What are good alternatives?

Take a look at fsarchiver

It can be found on the latest SystemRescueCD

Reportedly made by the same guy who authored partimage.

It sports a lot of improvements including: - ext4 support - ntfs support - file-level instead of block-level - compression using multiple cores

Basically, after a partition is saved/compressed it can be restored to different size partitions, and partitions of different formats (so you can use it to convert a partition's format too), and if part of the backup gets corrupted it doesn't destroy the whole image (like it would on a block-level backup.

The only downside (if you consider it a downside) is, it's only a command line app at the moment (but it should get a gui eventually).

The command line entries are really simple.

To save a partition:

fsarchiver savefs /mnt/backup/gentoo-rootfs.fsa /dev/sda1

Where '/mnt/backup/gentoo-rootfs.fsa' is the path being saved to and '/dev/sda1' is the partition being cloned.

To restore a partition:

fsarchiver restfs /mnt/backup/gentoo-rootfs.fsa id=0,dest=/dev/sda1

Just reverse the options above. From what I understand (in the documentation), it looks like the id=0 is necessary because an image can contain multiple partitions. For more directions on usage (such as saving multiple partitions) checkout the QuickStart guide.

SideNote:

As it turns out, I'm actually writing this (as entertainment) from a Linux Mint LiveCD while I'm cloning a newly updated windows factory install clone. I scoured the net earlier looking for a better partition cloning alternative because I want to finally trash this Ghose '03 disc that I've been using for years. I'll drop a note to let you know how it went after I finish the restore.

Update:

Just finished the backup with no errors. It took a little while because I didn't know about the options to make it multi-threaded when I started. The compression was set to the default value (equivalent to gzip -6), the partition was 4.48GB on disk (highly trimmed/updated XP + Chrome) and the output file weighs in at 2.3GB. No complaints here.

Try Clonezilla. It runs in a liveCD environment, and supports any sort of partition (including ext4), to a variety of stores (NFS, SMB, SSH, local filesystems).

I use it all the time to image workstations in our labs.