title: Do I have to wait for reshaping to call resize2fs after mdadm raid 5 grow?
body: <p>The title says it all.
  I have a 3 partitions mdadm raid 5 on ubuntu.
  Now I added a 4th partition.
  All partitions cover the full physical disk, each disk is 4 TB in size.
  The Filesystem in use is ext4.</p>
  
  <p>After mdadm growing the raid 5 the wiki says to make an fsck check and then resize</p>
  
  <p>Do I have to wait for the mdadm reshape to finish for the resize2fs to work?
  If not it doesn't seem to work.
  the raid is unmounted of course.
  I did the fsck -f check.
  ran resize2fs on the raid
  but mdadm -D /dev/md0 still shows 4 disks with Array size 8 TB and dev size 4 TB.
  fdisk -l also shows only a size of 8 TB.</p>
  
  <p>Did i do something wrong?
  How can i resize the filesystem to include my 4th disk?</p>
  
  <p>fdisk -l output:</p>
  
  <pre><code>Disk /dev/sdb: 3.7 TiB, 4000787030016 bytes, 7814037168 sectors
  Units: sectors of 1 * 512 = 512 bytes
  Sector size (logical/physical): 512 bytes / 4096 bytes
  I/O size (minimum/optimal): 4096 bytes / 4096 bytes
  Disklabel type: gpt
  Disk identifier: E434C200-63C3-4CB8-8097-DD369155D797
  
  Device     Start        End    Sectors  Size Type
  /dev/sdb1   2048 7814035455 7814033408  3.7T Linux RAID
  
  
  Disk /dev/sdd: 3.7 TiB, 4000787030016 bytes, 7814037168 sectors
  Units: sectors of 1 * 512 = 512 bytes
  Sector size (logical/physical): 512 bytes / 4096 bytes
  I/O size (minimum/optimal): 4096 bytes / 4096 bytes
  Disklabel type: gpt
  Disk identifier: CAD9D9DA-1C3B-4FC2-95BD-A5F0B55DE313
  
  Device     Start        End    Sectors  Size Type
  /dev/sdd1   2048 7814035455 7814033408  3.7T Linux RAID
  
  
  Disk /dev/sdc: 3.7 TiB, 4000787030016 bytes, 7814037168 sectors
  Units: sectors of 1 * 512 = 512 bytes
  Sector size (logical/physical): 512 bytes / 4096 bytes
  I/O size (minimum/optimal): 4096 bytes / 4096 bytes
  Disklabel type: gpt
  Disk identifier: 090E94F6-A461-4B27-BCDF-5B49EC6AFC84
  
  Device     Start        End    Sectors  Size Type
  /dev/sdc1   2048 7814035455 7814033408  3.7T Linux RAID
  
  
  Disk /dev/sde: 3.7 TiB, 4000787030016 bytes, 7814037168 sectors
  Units: sectors of 1 * 512 = 512 bytes
  Sector size (logical/physical): 512 bytes / 4096 bytes
  I/O size (minimum/optimal): 4096 bytes / 4096 bytes
  Disklabel type: gpt
  Disk identifier: A0285071-2C16-42B4-8567-32CE98147A93
  
  Device     Start        End    Sectors  Size Type
  /dev/sde1   2048 7814035455 7814033408  3.7T Linux RAID
  
  
  Disk /dev/md0: 7.3 TiB, 8001301774336 bytes, 15627542528 sectors
  Units: sectors of 1 * 512 = 512 bytes
  Sector size (logical/physical): 512 bytes / 4096 bytes
  I/O size (minimum/optimal): 524288 bytes / 1572864 bytes
  </code></pre>
  
  <p>mdadm -D /dev/md0 output</p>
  
  <pre><code>/dev/md0:
          Version : 1.2
    Creation Time : Thu Jan  7 08:23:57 2016
       Raid Level : raid5
       Array Size : 7813771264 (7451.79 GiB 8001.30 GB)
    Used Dev Size : 3906885632 (3725.90 GiB 4000.65 GB)
     Raid Devices : 4
    Total Devices : 4
      Persistence : Superblock is persistent
  
    Intent Bitmap : Internal
  
      Update Time : Mon Jan 11 08:10:47 2016
            State : clean, reshaping 
   Active Devices : 4
  Working Devices : 4
   Failed Devices : 0
    Spare Devices : 0
  
           Layout : left-symmetric
       Chunk Size : 512K
  
   Reshape Status : 47% complete
    Delta Devices : 1, (3-&gt;4)
  
             Name : NAS:0  (local to host NAS)
             UUID : 69ba4b0e:a2427b2a:121cc4e0:5461a8fb
           Events : 10230
  
      Number   Major   Minor   RaidDevice State
         0       8       33        0      active sync   /dev/sdc1
         1       8       49        1      active sync   /dev/sdd1
         3       8       65        2      active sync   /dev/sde1
         4       8       17        3      active sync   /dev/sdb1
  </code></pre>