title: add rule to firewalld in Centos7 to allow all traffic from a server
body: <p>I have a small cluster with Centos7. I'm trying how to use the new firewalld.</p>
  
  <p>I need a rule to allow all traffic between those servers.
  I was able to do it with:</p>
  
  <pre><code>sudo iptables -A INPUT -s [hostname] -j ACCEPT 
  </code></pre>
  
  <p>and it worked. But now I have to use firewall-cmd because of Centos 7. How can I  add a rule to allow all traffic between my nodes?
  I'm trying to run MPI on them but the firewalld is rejecting the connection so the solution I thought of came to this. </p>
  
  <p>My current firewall-cmd configuration is:</p>
  
  <pre><code>$ firewall-cmd --list-all
  work (default, active)
    interfaces: eno1
    sources:
    services: dhcpv6-client ipp-client ssh
    ports:
    masquerade: no
    forward-ports:
    icmp-blocks:
    rich rules:
  </code></pre>