dd cloing active disk.. safe?

[Dj_Jestar]

Hello chaps and chappettes.. I wish to clone the currently operational disk. I've used dd many times before, and am confident with it, but this disk is utterly important, so I wanted to check that using dd on it, in the form of:

# dd if=/dev/hda of=/dev/hdb

is not going to cause me any problems. /dev/hda is the disk that my gentoo install is running from. I.e. it has the /boot partition with the currently active kernel, and the swap partition that is currently in use.

Should I be wary?

 

[Dj_Jestar]

We skipped it, the two disks were too different in geometry to bother, so we tar'd the partitions and then cp'd to the new disk

 

[Dj_Jestar]

Yeah, it was reading from the active disk, writing to a slave.