[CentOS] Centos4: USB disk standby?

Mon Dec 15 09:27:33 UTC 2008
Rainer Traut <tr.ml at gmx.de>


I've decided to use an external USB disk as backup with rsync.
This works fine.

When the external disk is mounted, it does not go into 
standby/sleep/whatever, though I'm using it only for 30minutes at night.

Is there a way to do this with C4, 2.6.9-78.0.8.ELsmp?
E.g. unmount/some special command/upgrade to 5.2?