code: def add_interface(zone, interface, permanent=True):
      '''
      Bind an interface to a zone
  
      .. versionadded:: 2016.3.0
  
      CLI Example:
  
      .. code-block:: bash
  
          salt '*' firewalld.add_interface zone eth0
      '''
      if interface in get_interfaces(zone, permanent):
          log.info('Interface is already bound to zone.')
  
      cmd = '--zone={0} --add-interface={1}'.format(zone, interface)
  
      if permanent:
          cmd += ' --permanent'
  
      return __firewall_cmd(cmdf add_interface(zone, interface, permanent=True):
      '''
      Bind an interface to a zone
  
      .. versionadded:: 2016.3.0
  
      CLI Example:
  
      .. code-block:: bash
  
          salt '*' firewalld.add_interface zone eth0
      '''
      if interface in get_interfaces(zone, permanent):
          log.info('Interface is already bound to zone.')
  
      cmd = '--zone={0} --add-interface={1}'.format(zone, interface)
  
      if permanent:
          cmd += ' --permanent'
  
      return __firewall_cmd(cmd)
docs: Bind an interface to a zone
  
      .. versionadded:: 2016.3.0
  
      CLI Example:
  
      .. code-block:: bash
  
          salt '*' firewalld.add_interface zone eth0