I am having problems creating a RAID 5 array using 3x400GB SATA drives on a Dell SC430 running Xandros 4. I created this once with Webmin and it worked OK but then I deleted it and started again as I believe the chunk size was too small at 4kb, the default size with Webmin. I have repartitioned and formatted the drives. I have tried creating the array with Webmin and at the console but it always fails with the same error. This is the command I use: mdadm --create --verbose /dev/md0 --level=raid5 --chunk=256 --run --raid-devices=3 /dev/sdb1 /dev/sdc1 /dev/sdd1 mdadm: layout defaults to left-symmetric mdadm: /dev/sdb1 appears to contain an ext2fs file system size=390708800K mtime=Wed Dec 31 19:00:00 1969 mdadm: /dev/sdc1 appears to contain an ext2fs file system size=390708800K mtime=Wed Dec 31 19:00:00 1969 mdadm: /dev/sdd1 appears to contain an ext2fs file system size=390708800K mtime=Wed Dec 31 19:00:00 1969 mdadm: size set to 390708736K mdadm: creation continuing despite oddities due to --run mdadm: SET_ARRAY_INFO failed for /dev/md0: Device or resource busy This is the output from fdisk -l : Disk /dev/sdb: 400.0 GB, 400088457216 bytes 255 heads, 63 sectors/track, 48641 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/sdb1 1 48641 390708801 fd Linux raid autodetect Disk /dev/sdc: 400.0 GB, 400088457216 bytes 255 heads, 63 sectors/track, 48641 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/sdc1 1 48641 390708801 fd Linux raid autodetect Disk /dev/sdd: 400.0 GB, 400088457216 bytes 255 heads, 63 sectors/track, 48641 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/sdd1 1 48641 390708801 fd Linux raid autodetect Why does it always give the error "Device or resource busy", and what can I do about it? - Ray Greene - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html