> > Is there a GUI like Disk Druid for initializing hard drives in > software RAID 1 *after* the system has been installed? > no need - " 5.6 RAID-1 You have two devices of approximately same size, and you want the two to be mirrors of each other. Eventually you have more devices, which you want to keep as stand-by spare-disks, that will automatically become a part of the mirror if one of the active devices break. Set up the |/etc/raidtab| file like this: raiddev /dev/md0 raid-level 1 nr-raid-disks 2 nr-spare-disks 0 persistent-superblock 1 device /dev/sdb6 raid-disk 0 device /dev/sdc5 raid-disk 1 If you have spare disks, you can add them to the end of the device specification like device /dev/sdd5 spare-disk 0 Remember to set the |nr-spare-disks| entry correspondingly. Ok, now we're all set to start initializing the RAID. The mirror must be constructed, eg. the contents (however unimportant now, since the device is still not formatted) of the two devices must be synchronized. Issue the mkraid /dev/md0 command to begin the mirror initialization. Check out the |/proc/mdstat| file. It should tell you that the /dev/md0 device has been started, that the mirror is being reconstructed, and an ETA of the completion of the reconstruction. Reconstruction is done using idle I/O bandwidth. So, your system should still be fairly responsive, although your disk LEDs should be glowing nicely. The reconstruction process is transparent, so you can actually use the device even though the mirror is currently under reconstruction. Try formatting the device, while the reconstruction is running. It will work. Also you can mount it and use it while reconstruction is running. Of Course, if the wrong disk breaks while the reconstruction is running, you're out of luck." Taken from http://tldp.org/HOWTO/Software-RAID-HOWTO-5.html _______________________________________________ CentOS mailing list CentOS@xxxxxxxxxx http://lists.centos.org/mailman/listinfo/centos