<div dir="ltr"><div class="gmail_default" style="font-family:verdana,sans-serif">you are welcome. </div><div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">you can refer following codes to make a raid 0 volume</div><div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif"><pre class="" style="font-family:Consolas,&#39;Liberation Mono&#39;,Menlo,Courier,monospace;font-size:12px;margin-top:0px;margin-bottom:0px;width:1056px;color:rgb(51,51,51);line-height:13.4399995803833px"><div class="" id="file-create_raid0-sh-LC6"><span class="" style="color:rgb(150,152,150)">#You can list the devices</span>
</div><div class="" id="file-create_raid0-sh-LC7">lsblk
</div><div class="" id="file-create_raid0-sh-LC8"><span class="" style="color:rgb(150,152,150)">#(RAID 0 only) To create a RAID 0 array, execute the following command (note the --level=stripe option to stripe the array):  </span>
</div><div class="" id="file-create_raid0-sh-LC9">sudo mdadm --create --verbose /dev/md0 --level=stripe --raid-devices=<span class="">$number_of_volumes</span> <span class="">$device_name1</span> <span class="">$device_name2</span> 
</div><div class="" id="file-create_raid0-sh-LC10"><span style="color:rgb(150,152,150)">#For example, to create an ext4 file system, execute the following command:  </span><br></div><div class="" id="file-create_raid0-sh-LC14">sudo mkfs.ext4 /dev/md0 
</div><div><br></div></pre></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Tue, Dec 9, 2014 at 11:42 AM, Jian Feng <span dir="ltr">&lt;<a href="mailto:freedafeng@yahoo.com" target="_blank">freedafeng@yahoo.com</a>&gt;</span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><div style="color:#000;background-color:#fff;font-family:HelveticaNeue,Helvetica Neue,Helvetica,Arial,Lucida Grande,sans-serif;font-size:16px"><div><span>Thanks Jennifer and Jin!</span></div><div style="color:rgb(0,0,0);font-size:16px;font-family:HelveticaNeue,&#39;Helvetica Neue&#39;,Helvetica,Arial,&#39;Lucida Grande&#39;,sans-serif;font-style:normal;background-color:transparent"><span><br></span></div><div style="color:rgb(0,0,0);font-size:16px;font-family:HelveticaNeue,&#39;Helvetica Neue&#39;,Helvetica,Arial,&#39;Lucida Grande&#39;,sans-serif;font-style:normal;background-color:transparent"><span>You are definitely right. The svdaa is one of the two ssds and it is mounted to /mnt. The other ssd (/dev/svdab) is in the list, but not mounted to anywhere. I am wondering if there is a way to add the other svdab disk to /mnt to make a 37*2 GB disk, (as Jin mentioned). really appreciated your help.</span></div><div style="color:rgb(0,0,0);font-size:16px;font-family:HelveticaNeue,&#39;Helvetica Neue&#39;,Helvetica,Arial,&#39;Lucida Grande&#39;,sans-serif;font-style:normal;background-color:transparent"><span><br></span></div><div class="hm HOEnZb"><div><br></div>  </div><div style="font-family:HelveticaNeue,&#39;Helvetica Neue&#39;,Helvetica,Arial,&#39;Lucida Grande&#39;,sans-serif;font-size:16px"><div class="hm HOEnZb"> </div><div style="font-family:HelveticaNeue,&#39;Helvetica Neue&#39;,Helvetica,Arial,&#39;Lucida Grande&#39;,sans-serif;font-size:16px"><div class="hm HOEnZb"> <div dir="ltr"> <hr size="1">  <font face="Arial"> <b><span style="font-weight:bold">From:</span></b> Jennifer Staab &lt;<a href="mailto:jstaab@cs.unc.edu" target="_blank">jstaab@cs.unc.edu</a>&gt;<br> <b><span style="font-weight:bold">To:</span></b> Jian Feng &lt;<a href="mailto:freedafeng@yahoo.com" target="_blank">freedafeng@yahoo.com</a>&gt; <br><b><span style="font-weight:bold">Cc:</span></b> &quot;<a href="mailto:starcluster@mit.edu" target="_blank">starcluster@mit.edu</a>&quot; &lt;<a href="mailto:starcluster@mit.edu" target="_blank">starcluster@mit.edu</a>&gt; <br> <b><span style="font-weight:bold">Sent:</span></b> Tuesday, December 9, 2014 8:24 AM<br> <b><span style="font-weight:bold">Subject:</span></b> Re:
 [StarCluster] need scratch space<br> </font> </div></div><div><div class="h5"> <div><br><div><div>
    <div>Submit command &quot;lsblk&quot; and you will see
      the instance/ephemeral storage.  In my experience the
      instance/ephemeral storage will be smaller in size ( for me 40 GB
      is typically 37.5/37 GB in size) and usually one disk is
      automatically mounted as &quot;/mnt&quot;.  Seems like in your case it is
      likely &quot;/dev/xvdaa&quot; is one of the instance/ephemeral disks.  If
      you don&#39;t see the other with &quot;lsblk&quot; command, it is likely when
      you created the EC2 you forgot to indicate you wanted to use both
      instance storage disks when you added storage to your EC2.<br clear="none">
      <br clear="none">
      Good Luck.<br clear="none">
      <br clear="none">
      - Jennifer <br clear="none">
      <br clear="none">
      On 12/9/14 9:48 AM, Jin Yu wrote:<br clear="none">
    </div>
    <blockquote type="cite">
      <div dir="ltr">
        <div style="font-family:verdana,sans-serif">You can use these two
          40G SSD to make a raid0 volume of 80G, and then mount it to
          /scratch. <br clear="none">
        </div>
        <div style="font-family:verdana,sans-serif"><br clear="none">
        </div>
        <div style="font-family:verdana,sans-serif">-Jin</div>
      </div>
      <div><br clear="none">
        <div>On Mon, Dec 8, 2014 at 1:55 PM, Jian
          Feng <span dir="ltr">&lt;<a rel="nofollow" shape="rect" href="mailto:freedafeng@yahoo.com" target="_blank">freedafeng@yahoo.com</a>&gt;</span>
          wrote:<br clear="none">
          <blockquote style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
            <div>
              <div style="color:rgb(0,0,0);font-family:HelveticaNeue,&#39;Helvetica Neue&#39;,Helvetica,Arial,&#39;Lucida Grande&#39;,sans-serif;font-size:16px;background-color:rgb(255,255,255)">
                <div>Dear starcluster community,</div>
                <div><br clear="none">
                </div>
                <div style="color:rgb(0,0,0);font-size:16px;font-family:HelveticaNeue,&#39;Helvetica                   Neue&#39;,Helvetica,Arial,&#39;Lucida                   Grande&#39;,sans-serif;font-style:normal;background-color:transparent">I
                  created an ec2 cluster using m3.xlarge instance
                  (2*40GB SSD). I did not see any scratch space or
                  /scratch folder at all. Here is the disk space
                  layout. </div>
                <div style="color:rgb(0,0,0);font-size:16px;font-family:HelveticaNeue,&#39;Helvetica                   Neue&#39;,Helvetica,Arial,&#39;Lucida                   Grande&#39;,sans-serif;font-style:normal;background-color:transparent"><br clear="none">
                </div>
                <div style="background-color:transparent">root@node001:~#
                  df -h</div>
                <div style="background-color:transparent">Filesystem    
                     Size  Used Avail Use% Mounted on</div>
                <div style="background-color:transparent">/dev/xvda1    
                      20G  5.6G   14G  30% /</div>
                <div style="background-color:transparent">udev          
                     7.4G  8.0K  7.4G   1% /dev</div>
                <div style="background-color:transparent">tmpfs        
                      3.0G  176K  3.0G   1% /run</div>
                <div style="background-color:transparent">none          
                     5.0M     0  5.0M   0% /run/lock</div>
                <div style="background-color:transparent">none          
                     7.4G     0  7.4G   0% /run/shm</div>
                <div style="background-color:transparent">/dev/xvdaa    
                      37G  177M   35G   1% /mnt</div>
                <div style="background-color:transparent">master:/home  
                      20G  5.6G   14G  30% /home</div>
                <div style="background-color:transparent">master:/opt/sge6
                    20G  5.6G   14G  30% /opt/sge6</div>
                <div style="background-color:transparent"><br clear="none">
                </div>
                <div style="color:rgb(0,0,0);font-size:16px;font-family:HelveticaNeue,&#39;Helvetica                   Neue&#39;,Helvetica,Arial,&#39;Lucida                   Grande&#39;,sans-serif;font-style:normal;background-color:transparent">In
                  my application, I need a scatch folder on each node
                  that has about 50G space. Is there a way to do that? I
                  don&#39;t really need /home or /opt/sge6 stuff. And I
                  don&#39;t run mpi applications. </div>
                <div style="color:rgb(0,0,0);font-size:16px;font-family:HelveticaNeue,&#39;Helvetica                   Neue&#39;,Helvetica,Arial,&#39;Lucida                   Grande&#39;,sans-serif;font-style:normal;background-color:transparent"><br clear="none">
                </div>
                <div style="color:rgb(0,0,0);font-size:16px;font-family:HelveticaNeue,&#39;Helvetica                   Neue&#39;,Helvetica,Arial,&#39;Lucida                   Grande&#39;,sans-serif;font-style:normal;background-color:transparent">Maybe
                  I should recreate an AMI?</div>
                <div style="color:rgb(0,0,0);font-size:16px;font-family:HelveticaNeue,&#39;Helvetica                   Neue&#39;,Helvetica,Arial,&#39;Lucida                   Grande&#39;,sans-serif;font-style:normal;background-color:transparent"><br clear="none">
                </div>
                <div style="color:rgb(0,0,0);font-size:16px;font-family:HelveticaNeue,&#39;Helvetica                   Neue&#39;,Helvetica,Arial,&#39;Lucida                   Grande&#39;,sans-serif;font-style:normal;background-color:transparent">Thanks!</div>
                <div style="color:rgb(0,0,0);font-size:16px;font-family:HelveticaNeue,&#39;Helvetica                   Neue&#39;,Helvetica,Arial,&#39;Lucida                   Grande&#39;,sans-serif;font-style:normal;background-color:transparent"><br clear="none">
                </div>
                <div><br clear="none">
                </div>
                <div style="color:rgb(0,0,0);font-size:16px;font-family:HelveticaNeue,&#39;Helvetica                   Neue&#39;,Helvetica,Arial,&#39;Lucida                   Grande&#39;,sans-serif;font-style:normal;background-color:transparent"><br clear="none">
                </div>
              </div>
            </div>
            <br clear="none">
            _______________________________________________<br clear="none">
            StarCluster mailing list<br clear="none">
            <a rel="nofollow" shape="rect" href="mailto:StarCluster@mit.edu" target="_blank">StarCluster@mit.edu</a><br clear="none">
            <a rel="nofollow" shape="rect" href="http://mailman.mit.edu/mailman/listinfo/starcluster" target="_blank">http://mailman.mit.edu/mailman/listinfo/starcluster</a><div><br><br></div><div><br clear="none">
            <br clear="none">
          </div></blockquote><div>
        </div></div><div>
        <br clear="none">
      </div></div><div>
      <br clear="none">
      <fieldset></fieldset>
      <br clear="none">
      <pre>_______________________________________________
StarCluster mailing list
<a rel="nofollow" shape="rect" href="mailto:StarCluster@mit.edu" target="_blank">StarCluster@mit.edu</a>
<a rel="nofollow" shape="rect" href="http://mailman.mit.edu/mailman/listinfo/starcluster" target="_blank">http://mailman.mit.edu/mailman/listinfo/starcluster</a>
</pre>
    </div></blockquote><div>
    <br clear="none">
  </div></div></div><br><br></div> </div></div></div> </div>  </div></div><br>_______________________________________________<br>
StarCluster mailing list<br>
<a href="mailto:StarCluster@mit.edu">StarCluster@mit.edu</a><br>
<a href="http://mailman.mit.edu/mailman/listinfo/starcluster" target="_blank">http://mailman.mit.edu/mailman/listinfo/starcluster</a><br>
<br></blockquote></div><br></div>