Comment 1 for bug 149918

Same problem here. Couple errors.

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The kernel was unable to re-read the partition table on /dev/md0 (Invalid argument). This means Linux won't know anything about the modifications you made until you reboot. You should reboot your computer before doing anything with /dev/md0.
The kernel was unable to re-read the partition table on /dev/md0 (Invalid argument). This means Linux won't know anything about the modifications you made until you reboot. You should reboot your computer before doing anything with /dev/md0.

$ sudo fdisk -l

Disk /dev/sda: 250.9 GB, 250999111168 bytes
255 heads, 63 sectors/track, 30515 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x7acdb905

   Device Boot Start End Blocks Id System
/dev/sda1 * 1 5737 46082421 7 HPFS/NTFS
/dev/sda2 5738 6746 8104792+ 83 Linux
/dev/sda3 6747 7962 9767520 fd Linux raid autodetect
/dev/sda4 7963 30515 181156972+ fd Linux raid autodetect

Disk /dev/sdb: 250.0 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0xb45eb45e

   Device Boot Start End Blocks Id System
/dev/sdb1 1 1216 9767488+ fd Linux raid autodetect
/dev/sdb2 1217 23768 181148940 fd Linux raid autodetect
/dev/sdb3 23769 24984 9767520 82 Linux swap / Solaris
/dev/sdb4 24985 30401 43512052+ 7 HPFS/NTFS

Disk /dev/sdc: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x000d6c90

   Device Boot Start End Blocks Id System
/dev/sdc1 1 37028 297427378+ 83 Linux
/dev/sdc2 37029 38244 9767520 fd Linux raid autodetect
/dev/sdc3 38245 60801 181189102+ fd Linux raid autodetect

Disk /dev/md0: 20.0 GB, 20003684352 bytes
2 heads, 4 sectors/track, 4883712 cylinders
Units = cylinders of 8 * 512 = 4096 bytes
Disk identifier: 0x00000000

Disk /dev/md0 doesn't contain a valid partition table

Disk /dev/md1: 370.9 GB, 370992873472 bytes
2 heads, 4 sectors/track, 90574432 cylinders
Units = cylinders of 8 * 512 = 4096 bytes
Disk identifier: 0x00000000

Disk /dev/md1 doesn't contain a valid partition table