9

I've created an EC2 instance, created an EBS volume, attached it to the running instance, and successfully ssh'ed into my instance.

The drive is attached as /dev/sdf

Next, I tried mounting the drive by running:

mkdir /testName
mount -t ext3 /dev/sdf /testName

But then I get the error message:

mount: wrong fs type, bad option, bad superblock on /dev/sdf,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail  or so

What am I doing wrong?

Thanks.

  • 1
    Did you try running "dmesg | tail" to see the error message ? – Shyam Sundar C S Mar 9 '12 at 18:32
15

Here's a complete set of commands that you should run once you've attached the EBS volume to your EC2 instance:

mkfs -t ext3 /dev/sdf   # (NOTE - if you created your EBS volume from a snapshot of another volume and want to preserve its data, skip this step)
echo "/dev/sdf  /testName  ext3     noatime  0 0" >> /etc/fstab
mkdir /testName
mount /testName
df -h                   # (you should now see a new /testName file system mounted on the EBS volume)
  • i was able to mount without partition, once partitioned each requires mkfs then able to mount with partition, thanks – vels4j Jan 25 '17 at 11:18
  • 1
    This worked perfectly. Please use this answer. – SmallChess Sep 4 '18 at 14:05
6

I had the same problem while mounting an EBS volume that I had taken a snapshot of. The gotcha was that when I attached the volume (e.g., /dev/sdf), it was actually partitioned so (/dev/sdf1) was also created. I was able to mount /dev/sdf1 with no problem.

  • This was the answer. – Shatiz Oct 25 '15 at 12:10
5

Have you created the filesystem yet?

mkfs -t ext3 /dev/sdf
0

In fact unless it is a snapshot, as an uninitialised block device, you may need to..

  • Create a partition table
  • Label the volume
  • Create partitions (at least 1)
  • Create a file system on your partition
  • Format the file system if required

None of these are strictly necessary if you do not want a filesystem, if you are only storing one file or stream (tar or dd style).

These options provide us with a great deal of control, and are the same tasks one would perform when installing a "clean" drive on your own metal.

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