LinuxQuestions.org - mdadm Rebuilding Raid 1 on 2 new disks problems

Hi All,
I had a mdadm raid-1 with 4 devices (md0, md1, md2 and md3) on two 300GB disks. I failed, and removed 1 disk and replaced it with a 1Tb disk. I partitioned the disk the same as the original and re-built (added) the array one device at a time with the new disk. Everything seemed to go OK.

I went ahead and failed and removed the other 300GB disk and added the 2nd 1Tb disk. I partitioned the disk the same as the original and rebuilt the array one device at a time. Again, went OK but the md3 array was not using the full size of the 1TB disks.

On the original disks md3 was built on top of an extended partition, (sda4 and sdb4) with a logical partition on top, (sda5 and sdb5). I tried to replicate that on the new disks, but it appears I didn't. mdstat and parted are not showing the same info, see below:

Code:

[root@pequod ~]# cat /proc/mdstat

Personalities : [raid1]

md3 : active raid1 sdb5[3]

      265135104 blocks super 1.1 [2/1] [_U]

      bitmap: 2/2 pages [8KB], 65536KB chunk



md0 : active raid1 sda1[2] sdb1[3]

      102388 blocks super 1.0 [2/2] [UU]



md127 : active raid1 sdd[1] sdc[0]

      976631488 blocks super 1.2 [2/2] [UU]

      bitmap: 5/8 pages [20KB], 65536KB chunk



md2 : active raid1 sdb3[3] sda3[2]

      8190968 blocks super 1.1 [2/2] [UU]



md1 : active raid1 sdb2[3] sda2[2]

      20478908 blocks super 1.1 [2/2] [UU]

      bitmap: 1/1 pages [4KB], 65536KB chunk



unused devices: <none>

Code:

[root@pequod ~]# parted -l

Model: ATA ST1000NM0055-1V4 (scsi)

Disk /dev/sda: 1000GB

Sector size (logical/physical): 512B/512B

Partition Table: msdos



Number  Start  End    Size    Type    File system  Flags

 1      1049kB  106MB  105MB  primary  ext2        raid

 2      106MB  21.1GB  21.0GB  primary              raid

 3      21.1GB  29.5GB  8399MB  primary              raid

 4      29.5GB  1000GB  971GB  primary              raid





Model: ATA ST1000NM0055-1V4 (scsi)

Disk /dev/sdb: 1000GB

Sector size (logical/physical): 512B/512B

Partition Table: msdos



Number  Start  End    Size    Type    File system  Flags

 1      1049kB  106MB  105MB  primary  ext2        raid

 2      106MB  21.1GB  21.0GB  primary              raid

 3      21.1GB  29.5GB  8399MB  primary              raid

 4      29.5GB  1000GB  971GB  primary              raid



Model: Unknown (unknown)

Disk /dev/md1: 21.0GB

Sector size (logical/physical): 512B/512B

Partition Table: loop



Number  Start  End    Size    File system  Flags

 1      0.00B  21.0GB  21.0GB  ext4



Model: Unknown (unknown)

Disk /dev/md2: 8388MB

Sector size (logical/physical): 512B/512B

Partition Table: loop



Number  Start  End    Size    File system    Flags

 1      0.00B  8388MB  8388MB  linux-swap(v1)



Model: Unknown (unknown)

Disk /dev/md0: 105MB

Sector size (logical/physical): 512B/512B

Partition Table: loop



Number  Start  End    Size  File system  Flags

 1      0.00B  105MB  105MB  ext2



Model: Unknown (unknown)

Disk /dev/md3: 271GB

Sector size (logical/physical): 512B/512B

Partition Table: loop



Number  Start  End    Size  File system  Flags

 1      0.00B  271GB  271GB  ext3

During the final rebuild the md3 device would not allow me to add the sda disk. So how do I fix this: add the sda disk/partition and use the full size of the new disks? I have a backup of the data on md3 so I can wipe it if necessary. But I'd like to keep md0, md1 and md2 intact.

Sorry for the length! Any help is greatly appreciated! Thanks!