>> I have a 500GB Sata drive about 15% used I would like to make an exact >> copy of too another Sata 500GB drive as a spare. That way if >> something happens to the one in service I can plug in the spare >> quickly and restore one of the weekly backups without reinstalling the >> entire OS and all the little tweaks of setup on this mail/web server. >> >> How do I do this? That is make an exact bootable copy of a linux >> drive. Its running Centos 4.6 if that matters. >> > > > brute force approach... > > dd if=/dev/sda of=/dev/sdb bs=16384 > > that will copy the whole physical drive. I would do this in single user > mode (init 1) for best results, as any changes to the file system while a > copy is in progress will be inconsistent Can I use this to copy from a single 500GB SATA drive with only 54GB in use to a hardware RAID 1 drive of 300GB? The RAID will be two 300GB SATA drives. Matt