title: mkfs ext4 failing on Azure VM
body: <p>I have a VM running CenOS 6.3 on Azure. I'm following the steps in the Microsoft article to attach a disk (<a href="http://azure.microsoft.com/en-us/documentation/articles/virtual-machines-linux-how-to-attach-disk/#attachexisting" rel="nofollow">article</a>).</p>
  
  <p>When I run: sudo mkfs -t ext4 /dev/sdc1
  the process hangs indefinitely at "Writing superblocks and filesystem accounting information"</p>
  
  <p>If I start a new session and try mounting the partition it says:
  "mount: you must specify the filesystem type"</p>
  
  <p>I've upgraded and downgraded my VM in order to force a hardware switch. I've detached and re-attached new disks of various sizes. Same result each time.</p>
  
  <p>I'm guessing it must be either an error or setting on my OS that is causing the problem. Below is a full bash session. Any help would be very much appreciated!</p>
  
  <pre><code>[apper@apper ~]$ sudo grep SCSI /var/log/messages
  Apr 19 14:08:47 apper kernel: sd 3:0:0:0: [sdc] Attached SCSI disk
  Apr 19 14:19:38 apper kernel: sd 3:0:0:0: [sdc] Synchronizing SCSI cache
  Apr 19 14:22:58 apper kernel: SCSI subsystem initialized
  Apr 19 14:22:58 apper kernel: Block layer SCSI generic (bsg) driver version 0.4 loaded (major 252)
  Apr 19 14:22:58 apper kernel: sd 1:0:1:0: [sdb] Attached SCSI disk
  Apr 19 14:22:58 apper kernel: sd 0:0:0:0: [sda] Attached SCSI disk
  Apr 19 14:33:08 apper kernel: sd 3:0:0:0: [sdc] Attached SCSI disk
  Apr 19 14:40:16 apper kernel: sd 3:0:0:0: [sdc] Synchronizing SCSI cache
  Apr 19 14:47:11 apper kernel: SCSI subsystem initialized
  Apr 19 14:47:11 apper kernel: Block layer SCSI generic (bsg) driver version 0.4 loaded (major 252)
  Apr 19 14:47:11 apper kernel: sd 1:0:1:0: [sdb] Attached SCSI disk
  Apr 19 14:47:11 apper kernel: sd 0:0:0:0: [sda] Attached SCSI disk
  Apr 19 14:48:40 apper kernel: sd 3:0:0:0: [sdc] Attached SCSI disk
  [apper@apper ~]$ sudo fdisk /dev/sdc
  
  WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
           switch off the mode (command 'c') and change display units to
           sectors (command 'u').
  
  Command (m for help): n
  Command action
     e   extended
     p   primary partition (1-4)
  p
  Partition number (1-4): 1
  First cylinder (1-32635, default 1):
  Using default value 1
  Last cylinder, +cylinders or +size{K,M,G} (1-32635, default 32635):
  Using default value 32635
  
  Command (m for help): w
  The partition table has been altered!
  
  Calling ioctl() to re-read partition table.
  Syncing disks.
  [apper@apper ~]$ sudo mkfs -t ext4 /dev/sdc1
  mke2fs 1.41.12 (17-May-2010)
  Filesystem label=
  OS type: Linux
  Block size=4096 (log=2)
  Fragment size=4096 (log=2)
  Stride=0 blocks, Stripe width=0 blocks
  16384000 inodes, 65535151 blocks
  3276757 blocks (5.00%) reserved for the super user
  First data block=0
  Maximum filesystem blocks=4294967296
  2000 block groups
  32768 blocks per group, 32768 fragments per group
  8192 inodes per group
  Superblock backups stored on blocks:
          32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
          4096000, 7962624, 11239424, 20480000, 23887872
  
  Writing inode tables: done
  Creating journal (32768 blocks): done
  Writing superblocks and filesystem accounting information:
  </code></pre>