anchor.diff:  [Create a TCP Route with a Port](../devguide/deploy-apps/routes-domains.html#create-route-with-port)
   section of the _Configuring Routes and Domains_ topic.
   
  -### <a id="modify-ports"></a> Router Groups: Modify TCP port reservations
  +### <a id="modify-ports"></a> Modify TCP port reservations
   
   After deployment, you can modify the range of ports available for TCP routes
   using `cf curl` commands, as demonstrated with the commands below. These commands
  
positive.code:         "guid": "9d1c1da9-ed63-45e8-45ee-256f8579455c",
          "name": "default-tcp",
          "type": "tcp",
          "reservable\_ports": "60000-60098"
        }
      ]
    </pre>
  
  1. Modify the `reservable_ports`:
  
      <pre class="terminal">
      $ cf curl \
      -X PUT -d '{"reservable_ports":"1024-1199"}' \
      /routing/v1/router_groups/f7392031-a488-4890-8835-c4a038a3bded
      </pre>
  
negative.code: 1. (Optional) Decide on the number of TCP routes you want to support. For each
  TCP route, you must reserve a port. Configure your load balancer to forward the
  range of ports to the TCP routers. Skip this step if you have configured DNS to
  resolve the TCP domain name to an instance of the TCP router. For more details
  on configuring port reservations see the [Modify TCP port
  reservations](#modify-ports) section below.
  
  
  1. <%= partial vars.tcp_port %>
  
  