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Install of UCP on RHEL or CentOS results in error regarding ports are already in use on your host


Installing UCP on RHEL or CentOS results in the following error:

UCP: FATA[0009] The following required ports are already in use on your host - 12385, 443, 2376, 12376, 4789, 12379, 12381, 12380, 12386, 12382, 12383, 12384.  You may specify an alternative port number to 2376 with the --swarm-port argument.


First, verify that no other applications are running on any of the required ports.

Next, check if firewalld is enabled (most likely scenario). If it is, use the following steps to allow the required ports, restart the firewall, and restart Docker:

  1. Add ports to open in the firewall:
    for i in 12376 4789 12386 2376 443 12381 12380 12382 12383 12384 12385 12379 ; do
      echo adding $i to the firewall
      firewall-cmd --add-port=$i/tcp --permanent
  2. Restart the firewall:
    firewall-cmd –-reload
  3. Restart Docker:
    systemctl restart docker
  4. Start the UCP installation again.
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