title: The amount of disk used by each volume used in Amazon EC2 machine
body: <p>I have an EC2 instance with 2 EBS volumes (each 1000 GB), and I want to shrink their size to the proper size. The question is what is this "proper size".<br>
  Here is the locations of the volumes shown to me at the AWS page: 
  <a href="https://i.stack.imgur.com/F9B29.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/F9B29.png" alt="enter image description here"></a></p>
  
  <p>When I login to the machine I get amount of space used, I get: </p>
  
  <pre><code>[ec2-user@ip-xx-xx-xxx-xxx ~]$ df -h 
  Filesystem      Size  Used Avail Use% Mounted on
  /dev/xvda1     1008G  194G  814G  20% /
  devtmpfs         30G   60K   30G   1% /dev
  tmpfs            31G     0   31G   0% /dev/shm
  </code></pre>
  
  <p>If I go inside the <code>/dev</code> and do <code>ls</code> (among lots of things) I would see that: </p>
  
  <pre><code>lrwxrwxrwx  1 root root           5 Aug 20 00:50 root -&gt; xvda1
  lrwxrwxrwx  1 root root           4 Aug 20 00:50 sda -&gt; xvda
  lrwxrwxrwx  1 root root           5 Aug 20 00:50 sda1 -&gt; xvda1
  lrwxrwxrwx  1 root root           4 Aug 20 00:49 sdf -&gt; xvdf
  </code></pre>
  
  <ul>
  <li>First, why inside <code>dev</code> we have <code>xvda</code>, <code>xvda1</code>, xvdf'? (and why <code>sda</code>, <code>sda1</code>?) The console only talks about <code>sdf</code> and <code>xvda</code>. </li>
  <li>Second, in the output of <code>df -h</code>, <code>/dev/xvda1</code> seems to be only one of the EBS volumes (right?) If so, how can get the disk usage for the other EBS volume? </li>
  </ul>
  
  <p>Update: More info: </p>
  
  <pre><code>[ec2-user@ip-10-144-183-22 ~]$ lsblk
  NAME    MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
  xvda    202:0    0    1T  0 disk 
  └─xvda1 202:1    0 1024G  0 part /
  xvdf    202:80   0    1T  0 disk 
  
  
  [ec2-user@ip-10-144-183-22 ~]$ sudo fdisk -l | grep Disk
  WARNING: fdisk GPT support is currently new, and therefore in an experimental phase. Use at your own discretion.
  Disk /dev/xvda: 1099.5 GB, 1099511627776 bytes, 2147483648 sectors
  Disk label type: gpt
  Disk /dev/xvdf: 1099.5 GB, 1099511627776 bytes, 2147483648 sectors
  </code></pre>