mdadm failing to create RAID 5 HELP!!!

[Mercedes300]

I'm trying to create a RAID 5 array with 4 1TB SATA HDD. Following this (http://bfish.xaedalus.net/?p=188) guide, I formated and flagged the partitions as RAID with gparted.

This is the output of $sudo fdisk -l

user@computer:~$ sudo fdisk -l

Disk /dev/sda: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x0003f0d6

Device Boot Start End Blocks Id System
/dev/sda1 1 121601 976760001 fd Linux raid autodetect

Disk /dev/sdb: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x00025dd2

Device Boot Start End Blocks Id System
/dev/sdb1 1 121601 976760001 fd Linux raid autodetect

Disk /dev/sdc: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x00057108

Device Boot Start End Blocks Id System
/dev/sdc1 1 121601 976760001 fd Linux raid autodetect

Disk /dev/sdd: 1000.2 GB, 1000204886016 bytes
255 heads, 63 sectors/track, 121601 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x00024d81

Device Boot Start End Blocks Id System
/dev/sdd1 1 121601 976760001 fd Linux raid autodetect

Disk /dev/sde: 250.0 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0xc4946615

Device Boot Start End Blocks Id System
/dev/sde1 * 1 29164 234259798+ 83 Linux
/dev/sde2 29165 30401 9936202+ 5 Extended
/dev/sde5 29165 30401 9936171 82 Linux swap / Solaris
user@computer:~$


This is per the guide. As you can see, it doesn't think sdc1 and sdd1 exist... very annoying!

user@computer:~$ sudo mdadm --create --verbose /dev/md0 --level=5 --raid-devices=4 /dev/sda1 /dev/sdb1 dev/sdc1 dev/sdd1
mdadm: layout defaults to left-symmetric
mdadm: chunk size defaults to 64K
mdadm: /dev/sda1 appears to contain an ext2fs file system
size=976760000K mtime=Wed Nov 12 13:09:36 2008
mdadm: /dev/sdb1 appears to contain an ext2fs file system
size=976760000K mtime=Wed Dec 31 19:00:00 1969
mdadm: Cannot open dev/sdc1: No such file or directory
mdadm: Cannot open dev/sdd1: No such file or directory
mdadm: create aborted
user@computer:~$


I also created and added the line "DEVICE partitions" to /etc/mdadm/mdadm.conf and executed the command
sudo mdadm --detail --scan >> /etc/mdadm/mdadm.conf

Why doesn't it see dev/sdc1 or dev/sdd1? I can mount both partitions, and they both have a Lost+Found directory in them.

All help is much appreciated

[Mercedes300]

OK, working threw this, I found that I can just add the two devices that work, and grow the array later with this guide (http://scotgate.org/?p=107). I'll keep you updated as things progress.

cheers! :KS

[obg123]

Come on... Why do you think it does not find dev/sdc1 and dev/sdd1?

I would try /dev/sdc1 and /dev/sdd1 if I were you... ;)

[colskinet]

Come on... Why do you think it does not find dev/sdc1 and dev/sdd1?

I would try /dev/sdc1 and /dev/sdd1 if I were you... ;)

Bingo, I had exactly the same problem the other night, baffled me for a whole hour!

[fjgaude]

Bingo, I had exactly the same problem the other night, baffled me for a whole hour!

Well, tell us how you fixed it, or how you are now doing.

[Mercedes300]

!!!!!!!! NO WAY! How could I be so stupid! I just kept recalling the command instead of re-typing it!

Man, that was a big goof on my part!

thanks guys for pointing out my obvious blunder.

[fjgaude]

Yes, /dev/sda1 is not dev/sda1, and /dev/sda1 is not /dev/sda. <smile>