[root@ns1 /]# cat /proc/mdstat Personalities : [raid1] read_ahead 1024 sectors md1 : active raid1 hdc2[1] hda2[0](F) 77055680 blocks [2/1] [_U] md0 : active raid1 hda1[0] hdc1[1] 48064 blocks [2/2] [UU] unused devices: [root@ns1 /]# fdisk /dev/hdc The number of cylinders for this disk is set to 9729. There is nothing wrong with that, but this is larger than 1024, and could in certain setups cause problems with: 1) software that runs at boot time (e.g., old versions of LILO) 2) booting and partitioning software from other OSs (e.g., DOS FDISK, OS/2 FDISK) Command (m for help): p Disk /dev/hdc: 80.0 GB, 80026361856 bytes 255 heads, 63 sectors/track, 9729 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/hdc1 * 1 6 48163+ fd Linux raid autodetect /dev/hdc2 7 9599 77055772+ fd Linux raid autodetect /dev/hdc3 9600 9729 1044225 82 Linux swap Command (m for help): d Partition number (1-4): 1 Command (m for help): d Partition number (1-4): 2 Command (m for help): d Selected partition 3 Command action a toggle a bootable flag b edit bsd disklabel c toggle the dos compatibility flag d delete a partition l list known partition types m print this menu n add a new partition o create a new empty DOS partition table p print the partition table q quit without saving changes s create a new empty Sun disklabel t change a partition's system id u change display/entry units v verify the partition table w write table to disk and exit x extra functionality (experts only) Command (m for help): p Disk /dev/hdc: 80.0 GB, 80026361856 bytes 255 heads, 63 sectors/track, 9729 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System Command (m for help): w The partition table has been altered! Calling ioctl() to re-read partition table. WARNING: Re-reading the partition table failed with error 16: Device or resource busy. The kernel still uses the old table. The new table will be used at the next reboot. Syncing disks. [root@ns1 /]# reboot