[SOLVED] Problem mounting 15 x 1.5TB Raid6 array

[dfs019]

Hey im new to Linux. I'm running Debian 2.6.26-21lenny4 and I am trying to mount a 15 disk raid6 array made up of 1.5 TB hd's. After building and formatting the array I try to mount it and I recieve this error

mount: wrong fs type, bad option, bad superblock on /dev/md2,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail  or so

I was successfully able to build and mount the raid6 array's following exactly the same steps using only 13 of the drives but when i try 14 or 15 of the drives I recieve that error message.

Please help I've been stuck on this for a while.

[scathefire]

you using ext3? that would depend on your block size. 4 KB block size only allows like 16 TB, which is about 13 of those disks you are talking about. Anything larger is not supported with ext3, unless you are running an Alpha type system which can support 8 KB block size, and doubles the maximum partition size (32 TB)

[dfs019]

sorry i forgot to specify im using jfs for the raid

[scathefire]

again it will depend on your block size

Help -

[dfs019]

how do i check which block size im using?

[scathefire]

since you are not running AIX, it would be safe to assume 4096 (4k) since that is the default, and from what I can tell the only block size supported on Linux systems that are not AIX

[scathefire]

just out of curiosity, does your kernel have jfs support?

[dfs019]

Yeah and I had a 13 drive raid working with the jfs. I am following this build from the backblaze storage pod build and I am using all the same hardware and software they listed so there must be a way to get it to work... I hope.

[HROAdmin26]

Technical details required

A) What does syslog say? Anything?

B) Did you successfully create and start the RAID device (/dev/md2)?
- What does "cat /proc/mdstat" say?
- What does "mdadm --misc --detail /dev/md2" show?

C) How did you create the array? Manually using mdadm commands?

D) How did you partition the array? Did you use parted and ensure it's a GUID partition table (not msdos)?

E) What command did you use to create the filesystem - mkfs.jfs with what switches?

F) Since it's a new array/blank - if the RAID device is created/working, have you tried creating another filesystem? Try creating an XFS filesystem?

[scathefire]

i believe they are doing this: How To Build a Cheap Petabyte Server: Lessons Learned - OS / File System, Closing Thoughts

can you run this command?

uname -a

i'd like to see what it says just out of curiosity