title: EC2 VPC Instance - Ports are filtered
body: <p>I've configured my server with a default security group, which has the following Inbound rules:</p>
  
  <pre><code>| Type | Protocol | Port Range | Source |
  | All TCP | TCP | 0-65535 | 0.0.0.0/0 |
  | All UDP | UDP | 0-65535 | 0.0.0.0/0|
  </code></pre>
  
  <p>With these rules, netstat shows the following output:</p>
  
  <pre><code>netstat -atn
  Active Internet connections (servers and established)
  Proto Recv-Q Send-Q Local Address           Foreign Address         State      
  tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN     
  tcp        0      0 0.0.0.0:5432            0.0.0.0:*               LISTEN     
  tcp        0      0 0.0.0.0:1113            0.0.0.0:*               LISTEN     
  tcp        0      0 10.0.1.31:2113          0.0.0.0:*               LISTEN     
  tcp        0      0 127.0.0.1:2113          0.0.0.0:*               LISTEN     
  tcp        0      0 0.0.0.0:11300           0.0.0.0:*               LISTEN     
  tcp        0      0 0.0.0.0:11211           0.0.0.0:*               LISTEN     
  tcp        0      0 0.0.0.0:6379            0.0.0.0:*               LISTEN     
  tcp        0      0 0.0.0.0:80              0.0.0.0:*               LISTEN     
  tcp6       0      0 :::22                   :::*                    LISTEN     
  tcp6       0      0 :::5432                 :::*                    LISTEN     
  tcp6       0      0 :::3306                 :::*                    LISTEN     
  tcp6       0      0 :::6379                 :::*                    LISTEN  
  </code></pre>
  
  <p>So, in theory, I should be able to connect to port 1113 with TCP from any IP Address. But this is not working, the IP address is showing as filtered, as you can see in the following output:</p>
  
  <p>The only ports that seem to be OK (open and not filtered) are 22 &amp; 80. Here's the output I get when testing them with nmap:</p>
  
  <pre><code>PORT     STATE    SERVICE
  22/tcp   open     ssh
  80/tcp   open     http
  1113/tcp filtered ltp-deepspace
  2113/tcp filtered unknown
  3306/tcp filtered mysql
  6379/tcp filtered unknown
  </code></pre>
  
  <p>I even tried adding a custom inbound rule just for my IP and Port 1113, but the result is the same.</p>
  
  <p>I suspect that some firewall is blocking traffic on those PORTS in my instance, but I'm not sure how to check that.</p>
  
  <p>One thing to notice, is that this instance is in a Amazon VPC. However, the network ACL for this instance has the following inbound rule, that should allow income communications from all ports:</p>
  
  <pre><code>|Rule # | Type | Protocol | Port Range | Source | Allow / Deny |
  | 100 | ALL Traffic | ALL | ALL | 0.0.0.0/0 |ALLOW |
  </code></pre>
  
  <p>Any ideas on what could be the issue here?</p>
  
  <p>Thanks a lot for your help!</p>