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Before, I had four 1TB drives on a RAID array. I added two more 1TB drives to the array, let it do its rebuild and it is not showing the size increase when I mount it.

jacks@Gen2:~$ df -h /mnt/storage
Filesystem            Size  Used Avail Use% Mounted on
/dev/md1              2.7T  2.4T  219G  92% /mnt/storage

And mdadm says the size is 5TB (in the array size section)

jacks@Gen2:~$ sudo mdadm --detail /dev/md1
        Version : 00.90
  Creation Time : Sun Jan 31 21:02:19 2010
     Raid Level : raid5
     Array Size : 4883812480 (4657.57 GiB 5001.02 GB)
  Used Dev Size : 976762496 (931.51 GiB 1000.20 GB)
   Raid Devices : 6
  Total Devices : 6
Preferred Minor : 1
    Persistence : Superblock is persistent

    Update Time : Mon Mar 28 17:26:27 2011
          State : clean
 Active Devices : 6
Working Devices : 6
 Failed Devices : 0
  Spare Devices : 0

         Layout : left-symmetric
     Chunk Size : 64K

           UUID : dd0366aa:5d8c42d0:1568936c:fdc60ad9 (local to host Gen2)
         Events : 0.148852

    Number   Major   Minor   RaidDevice State
       0       8       48        0      active sync   /dev/sdd
       1       8       64        1      active sync   /dev/sde
       2       8       80        2      active sync   /dev/sdf
       3       8       96        3      active sync   /dev/sdg
       4       8      128        4      active sync   /dev/sdi
       5       8      112        5      active sync   /dev/sdh

What am I doing wrong? Also, here is mdadm.conf

jacks@Gen2:~$ cat /etc/mdadm/mdadm.conf 
# mdadm.conf
# Please refer to mdadm.conf(5) for information about this file.

# by default, scan all partitions (/proc/partitions) for MD superblocks.
# alternatively, specify devices to scan, using wildcards if desired.
DEVICE partitions

# auto-create devices with Debian standard permissions
CREATE owner=root group=disk mode=0660 auto=yes

# automatically tag new arrays as belonging to the local system
HOMEHOST <system>

# instruct the monitoring daemon where to send mail alerts

# definitions of existing MD arrays
ARRAY /dev/md0 level=raid1 num-devices=2 UUID=4defdfb7:b0e9caeb:a8118f28:a56b3edc
ARRAY /dev/md1 level=raid5 num-devices=6 UUID=dd0366aa:5d8c42d0:1568936c:fdc60ad9

# This file was auto-generated on Thu, 13 May 2010 22:57:02 -0400
# by mkconf $Id$
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up vote 1 down vote accepted

You'll need to expand the filesystem to fit the new size of the array. Depends which file system is in use, but for ext2/3 you'll unmount the disk then use resize2fs /dev/md1 - with no other arguments it will automatically resize to fill the available space.

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Of course, how basic of me. Thanks. – Jacks_Depression Mar 28 '11 at 21:51

Your filesystem and your MD array are two different concerns. Assuming you've correctly increased the system of your md array (which, on the face of it, it looks like you have), you'll now need to resize your filesystem to match that.

How you do that is dependent on the filesystem type, which I can't see above. If it's ext2/3 (and ext4 I think) you'd use resize2fs. If it's xfs, you'd use xfs_growfs

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You need to resize the filesystem on the partition. See resize2fs (if it is an extX filesystem).

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