title: How to solve: RPC: Port mapper failure - RPC: Unable to receive errno = Connection refused
body: <p>I'm trying to set up a NFS server.</p>
  
  <p>I have two programs server and client, I start the server which starts without errors, then I create a file with the client, the file is created correctly, but when I try to write something in that file I get the error:</p>
  
  <pre><code>call failed: RPC: Unable to receive; errno = Connection refused
  </code></pre>
  
  <p>And here is my <code>rpcinfo -p</code> output</p>
  
  <pre><code># rpcinfo -p
     program vers proto   port  service
      100000    4   tcp    111  portmapper
      100000    3   tcp    111  portmapper
      100000    2   tcp    111  portmapper
      100000    4   udp    111  portmapper
      100000    3   udp    111  portmapper
      100000    2   udp    111  portmapper
      100024    1   udp    662  status
      100024    1   tcp    662  status
      100005    1   udp    892  mountd
      100005    1   tcp    892  mountd
      100005    2   udp    892  mountd
      100005    2   tcp    892  mountd
      100005    3   udp    892  mountd
      100005    3   tcp    892  mountd
      100003    3   tcp   2049  nfs
      100003    4   tcp   2049  nfs
      100227    3   tcp   2049  nfs_acl
      100003    3   udp   2049  nfs
      100227    3   udp   2049  nfs_acl
      100021    1   udp  58383  nlockmgr
      100021    3   udp  58383  nlockmgr
      100021    4   udp  58383  nlockmgr
      100021    1   tcp  39957  nlockmgr
      100021    3   tcp  39957  nlockmgr
      100021    4   tcp  39957  nlockmgr
   536870913    1   udp    997
   536870913    1   tcp    999
  </code></pre>
  
  <p>Please does anyone know how can I solve this problem ?</p>
  
  <p><strong>NOTE:</strong> I am using my laptop as server and client at the same time.</p>