Have i got this right, your trying to make raid on a loopback device
(dev 07:00 and 07:01)
I didnt know you could do that, has anyone else dont this?
Anyay, sorry, but ho ideas from me, hope you get it working though.
Glenn McGrath
Patrik Rådman wrote:
>
> > Besides Tomas' suggestion (which sounds likely), you need a chunk-size line,
> > even with linear-raid.
>
> Ah! I added "chunk-size 4" to the raidtab, and now I can run mkraid. I think
> the HOWTO should be updated, the example for linear there doesn't have
> chunk-size...
>
> So now I have been able to test the new RAID code, but it still fails in the
> same way as the old code from 2.2.13. Take a look at this:
>
> </scratch/raidtools-0.90> # cat /proc/mdstat
> Personalities : [linear]
> read_ahead 1024 sectors
> md0 : active linear [dev 07:01][1] [dev 07:00][0] 665600 blocks 4k rounding
> unused devices: <none>
> </scratch/raidtools-0.90> # hd /dev/md0 | head -10
> 00000000: f8ffffff 00000000 00000000 00000000 00000000 ....................
> 00000014: 00000000 00000000 00000000 00000000 00000000 ....................
> *
> 000001f4: 00000000 00000000 00000000 f8ffffff 00000000 ....................
> 00000208: 00000000 00000000 00000000 00000000 00000000 ....................
> *
> 00038bf8: 00000000 00000000 41424344 45464748 41424344 ........ABCDEFGHABCD
> 00038c0c: 45464748 41424344 45464748 41424344 45464748 EFGHABCDEFGHABCDEFGH
> 00038c20: 00000000 00000000 00000000 00000000 00000000 ....................
> *
> </scratch/raidtools-0.90> # mkdosfs /dev/md0
> mkdosfs 0.4, 27th February 1997 for MS-DOS/FAT/FAT32 FS
> </scratch/raidtools-0.90> # hd /dev/md0 | head -10
> 00000000: eb3c906d 6b646f73 66730000 02200100 02000200 .<.mkdosfs... ......
> 00000014: 00f8a300 04000200 00000000 00501400 00002970 .............P....)p
> 00000028: 254d3820 20202020 20202020 20204641 54313620 %M8 FAT16
> 0000003c: 20200e1f be5b7cac 22c0740b 56b40ebb 0700cd10 ...[|.".t.V.......
> 00000050: 5eebf032 e4cd16cd 19ebfe54 68697320 6973206e ^..2.......This is n
> 00000064: 6f742061 20626f6f 7461626c 65206469 736b2e20 ot a bootable disk.
> 00000078: 20506c65 61736520 696e7365 72742061 20626f6f Please insert a boo
> 0000008c: 7461626c 6520666c 6f707079 20616e64 0d0a7072 table floppy and..pr
> 000000a0: 65737320 616e7920 6b657920 746f2074 72792061 ess any key to try a
> 000000b4: 6761696e 202e2e2e 200d0a00 00000000 00000000 gain ... ...........
> </scratch/raidtools-0.90> # mount -t msdos /dev/md0 /mnt
> mount: wrong fs type, bad option, bad superblock on /dev/md0,
> or too many mounted file systems
> </scratch/raidtools-0.90> # hd /dev/md0 | head -10
> 00000000: f8ffffff 00000000 00000000 00000000 00000000 ....................
> 00000014: 00000000 00000000 00000000 00000000 00000000 ....................
> *
> 000001f4: 00000000 00000000 00000000 f8ffffff 00000000 ....................
> 00000208: 00000000 00000000 00000000 00000000 00000000 ....................
> *
> 00038bf8: 00000000 00000000 41424344 45464748 41424344 ........ABCDEFGHABCD
> 00038c0c: 45464748 41424344 45464748 41424344 45464748 EFGHABCDEFGHABCDEFGH
> 00038c20: 00000000 00000000 00000000 00000000 00000000 ....................
> *
> </scratch/raidtools-0.90> #
>
> So, a filesystem is created, and then magically disappears again!
>
> - Patrik Rådman
