I am setting up a server to store my photos and I wanted to make it a very safe RAID. I selected 160 GB drives as the price is reasonable and put in two dual interface Promise ATA cards. I set up 5 160 GB drives as 4 RAID drives and one spare, the intention being it could lose a drive and still have a redundant drive to use for parity: [root@munster root]# cat /etc/raidtab raiddev /dev/md0 raid-level 5 nr-raid-disks 4 nr-spare-disks 1 persistent-superblock 1 parity-algorithm left-symmetric chunk-size 32 device /dev/hde1 raid-disk 0 device /dev/hdg1 raid-disk 1 device /dev/hdi1 raid-disk 2 device /dev/hdk1 raid-disk 3 device /dev/hdb1 spare-disk 0 When I run "cat /proc/mdstat " I get: Personalities : [raid5] read_ahead 1024 sectors md0 : active raid5 hdb1[4] hdk1[3] hdi1[2] hdg1[1] hde1[0] 468864768 blocks level 5, 32k chunk, algorithm 2 [4/4] [UUUU] [=>...................] resync = 7.8% (12315804/156288256) finish=232.3min speed=10324K/sec unused devices: <none> Does this mean the array is using all 5 disks? Here's the relevant section from dmesg SiS651 ATA 133 controller ide0: BM-DMA at 0xa400-0xa407, BIOS settings: hda:DMA, hdb:DMA ide1: BM-DMA at 0xa408-0xa40f, BIOS settings: hdc:pio, hdd:pio PDC20269: IDE controller at PCI slot 00:0e.0 PDC20269: chipset revision 2 PDC20269: not 100% native mode: will probe irqs later ide2: BM-DMA at 0x7000-0x7007, BIOS settings: hde:pio, hdf:pio ide3: BM-DMA at 0x7008-0x700f, BIOS settings: hdg:pio, hdh:pio PDC20268: IDE controller at PCI slot 00:10.0 PDC20268: chipset revision 2 PDC20268: not 100% native mode: will probe irqs later ide4: BM-DMA at 0x5400-0x5407, BIOS settings: hdi:pio, hdj:pio ide5: BM-DMA at 0x5408-0x540f, BIOS settings: hdk:pio, hdl:pio hda: Maxtor 2F040L0, ATA DISK drive hdb: WDC WD1600BB-00HTA0, ATA DISK drive blk: queue c03cdfe0, I/O limit 4095Mb (mask 0xffffffff) blk: queue c03ce124, I/O limit 4095Mb (mask 0xffffffff) hde: WDC WD1600JB-00EVA0, ATA DISK drive blk: queue c03ce8a8, I/O limit 4095Mb (mask 0xffffffff) hdg: WDC WD1600BB-00HTA0, ATA DISK drive blk: queue c03ced0c, I/O limit 4095Mb (mask 0xffffffff) hdi: WDC WD1600JB-00EVA0, ATA DISK drive blk: queue c03cf170, I/O limit 4095Mb (mask 0xffffffff) hdk: WDC WD1600JB-00EVA0, ATA DISK drive blk: queue c03cf5d4, I/O limit 4095Mb (mask 0xffffffff) ide0 at 0x1f0-0x1f7,0x3f6 on irq 14 ide2 at 0x8400-0x8407,0x8002 on irq 10 ide3 at 0x7800-0x7807,0x7402 on irq 10 ide4 at 0x6800-0x6807,0x6402 on irq 3 ide5 at 0x6000-0x6007,0x5802 on irq 3 hda: attached ide-disk driver. hda: host protected area => 1 hda: 80293248 sectors (41110 MB) w/2048KiB Cache, CHS=4998/255/63, UDMA(133) hdb: attached ide-disk driver. hdb: host protected area => 1 hdb: 312581808 sectors (160042 MB) w/2048KiB Cache, CHS=19457/255/63, UDMA(100) hde: attached ide-disk driver. hde: host protected area => 1 hde: 312581808 sectors (160042 MB) w/8192KiB Cache, CHS=19457/255/63, UDMA(100) hdg: attached ide-disk driver. hdg: host protected area => 1 hdg: 312581808 sectors (160042 MB) w/2048KiB Cache, CHS=19457/255/63, UDMA(100) hdi: attached ide-disk driver. hdi: host protected area => 1 hdi: 312581808 sectors (160042 MB) w/8192KiB Cache, CHS=19457/255/63, UDMA(100) hdk: attached ide-disk driver. hdk: host protected area => 1 hdk: 312581808 sectors (160042 MB) w/8192KiB Cache, CHS=19457/255/63, UDMA(100) ide-floppy driver 0.99.newide Partition check: hda: hda1 hda2 hda3 hdb: hdb1 hde: hde1 hdg: hdg1 hdi: hdi1 hdk: hdk1 ide-floppy driver 0.99.newide md: md driver 0.90.0 MAX_MD_DEVS=256, MD_SB_DISKS=27 md: Autodetecting RAID arrays. [events: 00000002] [events: 00000002] [events: 00000002] [events: 00000002] [events: 00000002] md: autorun ... md: considering hdk1 ... md: adding hdk1 ... md: adding hdi1 ... md: adding hdg1 ... md: adding hde1 ... md: adding hdb1 ... md: created md0 md: bind<hdb1,1> md: bind<hde1,2> md: bind<hdg1,3> md: bind<hdi1,4> md: bind<hdk1,5> md: running: <hdk1><hdi1><hdg1><hde1><hdb1> md: hdk1's event counter: 00000002 md: hdi1's event counter: 00000002 md: hdg1's event counter: 00000002 md: hde1's event counter: 00000002 md: hdb1's event counter: 00000002 md: md0: raid array is not clean -- starting background reconstruction kmod: failed to exec /sbin/modprobe -s -k md-personality-4, errno = 2 md: personality 4 is not loaded! md :do_md_run() returned -22 md: md0 stopped. md: unbind<hdk1,4> md: export_rdev(hdk1) md: unbind<hdi1,3> md: export_rdev(hdi1) md: unbind<hdg1,2> md: export_rdev(hdg1) md: unbind<hde1,1> md: export_rdev(hde1) md: unbind<hdb1,0> md: export_rdev(hdb1) md: ... autorun DONE. Chris Mason -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list