OpenSUSE :: Application To Backup Root Partition Prior To Tumbleweed

On my main work machine I have openSUSE 11.4 standard KDE on two partitions, standard root and standard /home. I'm going to add the Tumbleweed repos and follow the evolution of openSUSE until 11.5/12.0 is released.

But I cannot afford to have my main work machine off the air. So I want to back up the root parttiion each time I go a major upgrade from the Tumbleweed repos.

So I thought I would just image the root partition in compressed/reduced form to a USB drive prior to updating.

First I looked at Partimage but it doesn't do the EXT4 filesystem.

Second I thought about Clonezilla but it doesn't allow compression (it states that the target for the image must be at least as big as the source partition); thus DD is just as limited.

Third I looked at the System backup and restore facility in Yast but it seems to be undocumented (i.e. I can't find it.)

Then I thought why not just use cp because the root filesystem of 11.4 for me is only occupying 6Gb ATM. I propose to use "cp -a -u -v" from a live CD to copy the root files to a USB drive with an EXT4 partition.

So two questions:is there a flaw in backing up the system/root with "cp -a -u -v"
is there a better imaging software for a small job like this