Monday, November 11, 2013

Attach a new volume to EC2 Instance

This blog will talk about how to mount a new volume to an existing EC2 instance, though it is very straightforward & simple, but it's good to have a checklist ready with you so that you can do things in one go instead of searching here and there. The most important thing to take note of in this blog is that you have to do couple of manual operations apart from mounting the volume through AWS Web UI.

  1. Go to the AWS Volumes screen, create a new volume if not created already.
  2. Select Attach Volume in Actions button

  3. Choose the instance, to which this volume needs to be mounted

  4. Confirm the volume state changes from available to in-use
  5. Go to the AWS Instances screen, select the EC2 instance to which volume was attached
  6. Check the Block Devices in the details section you can see the new volume details their. Let’s say it is mounted at /dev/sdf.

  7. Now log in to the EC2 instance machine, you can’t see the mounted volume yet(it is like an external un-formatted hdd that is connected to a linux box)
  8. To make it usable execute below commands
sudo su -                              [Switch to superuser]
mkfs -t ext3 /dev/xvdf                      [Format the drive if it is a new volume]
mkdir /home/mettl/mongo                      [Simply create a new directory]
mount /dev/xvdf /home/mettl/mongo   [Mount the drive on newly created directory]
Make sure to change permissions according to how you use it.
  1. To mount EBS volumes automatically on startup add an entry in /etc/fstab
/dev/xvdf    /home/mettl/mongo    ext3    defaults,nobootwait,comment=cloudconfig    0    0

Hope you will find this blog useful, rest assured this is the starting point of a new series I would be talking about couple of other best practices such as why do you need to have this kind of setup, how you will upgrade volume in case of a running ec2-instance..