title: Can't connect to docker after resuming VM
body: <p>For some reason whenever I suspend my VM and resume it, I can no longer connect to the docker container that is hosted within the VM. Usually, I pass <code>-p 3000:3000</code> to the docker container so that I can access the rails instance within it and this works fine, but when I suspend the VM and resume it later, I can no longer connect to port 3000 even though it's listening within the docker image.</p>
  
  <p>This results in me having to reboot the VM as <code>service docker restart</code> does not change anything.</p>
  
  <p>Is there something else I should be looking at to resolve this issue? I've been suspending/resuming my VM with docker in it for quite awhile and have never run into this issue before.</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>To reproduce this issue, I simply resumed my VM and tried connecting to localhost port 3000 from the VM itself (not within the docker image) and it cannot connect. However, below shows that port 3000 is listening:</p>
  
  <pre><code>[root:kali:~/app]# curl http://localhost:3000
  curl: (56) Recv failure: Connection reset by peer
  [root:kali:~/app]# netstat -antp | grep -i listen
  tcp        0      0 127.0.0.1:43050         0.0.0.0:*               LISTEN      84770/autossh       
  tcp        0      0 0.0.0.0:111             0.0.0.0:*               LISTEN      1/systemd           
  tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      20478/sshd          
  tcp6       0      0 :::3000                 :::*                    LISTEN      32731/docker-proxy  
  tcp6       0      0 :::3001                 :::*                    LISTEN      32715/docker-proxy  
  tcp6       0      0 :::111                  :::*                    LISTEN      1/systemd           
  tcp6       0      0 :::22                   :::*                    LISTEN      20478/sshd 
  </code></pre>
  
  <p>From within docker, I can see that rails is working:</p>
  
  <pre><code>[root:77f444beafff:~/app]# rails s --binding 0.0.0.0
  =&gt; Booting Puma
  =&gt; Rails 5.2.3 application starting in development 
  =&gt; Run `rails server -h` for more startup options
  Puma starting in single mode...
  * Version 3.12.1 (ruby 2.5.1-p57), codename: Llamas in Pajamas
  * Min threads: 5, max threads: 5
  * Environment: development
  * Listening on tcp://0.0.0.0:3000
  Use Ctrl-C to stop
  
  </code></pre>
  
  <p>And here's the netstat from within docker:</p>
  
  <pre><code>[root:77f444beafff:~/app]# netstat -antp | grep -i listen
  tcp        0      0 0.0.0.0:6379            0.0.0.0:*               LISTEN      478/redis-server *: 
  tcp        0      0 0.0.0.0:3000            0.0.0.0:*               LISTEN      765/puma 3.12.1 (tc 
  tcp        0      0 127.0.0.1:5432          0.0.0.0:*               LISTEN      -                   
  tcp6       0      0 :::6379   
  </code></pre>
  
  <p>If I curl from within the docker image, I can see it hits the rails app just fine:</p>
  
  <pre><code>[root:77f444beafff:~/app]# curl http://localhost:3000/ -I
  HTTP/1.1 200 OK
  X-Frame-Options: SAMEORIGIN
  X-XSS-Protection: 1; mode=block
  X-Content-Type-Options: nosniff
  X-Download-Options: noopen
  X-Permitted-Cross-Domain-Policies: none
  Referrer-Policy: strict-origin-when-cross-origin
  Content-Type: text/html; charset=utf-8
  ETag: W/"5078d30a6c1a5f6fc5cb7f9a82cd89f5"
  Cache-Control: max-age=0, private, must-revalidate
  Set-Cookie: _vspm_session=Cace%2FN0zB%2F6QJOiietbuHxTHOMZUMuRmEukYqQTNaHQ91hskaN%2BPJzev0KdGUAAtYx9a35Mqdkr8eRkPdH4qOl6vOaCcPU0gy8s7IMfkb9VhRGPPbecepmI%2F9leA2dnD694P8ctXSBklOCnjhN0%3D--SglWrWvx3BFEAI3z--IkylACdXbR6eF27Hgn0Cgg%3D%3D; path=/; HttpOnly
  X-Request-Id: 29aa7251-f29a-4309-adec-6af479e7bd9b
  X-Runtime: 12.241723
  </code></pre>