Configuring Services

This topic describes how to use the CLI to configure services. You can also customize services by using the Services tab in the DC/OS™ UI.

1. View the available configuration options for the service with the dcos package describe --config <package-name> command.

   dcos package describe --config marathon
   

   The output should appear similar to the following:

   {
   ...
     "service": {
       "additionalProperties": false,
       "description": "Marathon® app configuration properties.",
       "properties": {
         "cpus": {
           "default": 2,
           "description": "CPU shares to allocate to each Marathon instance.",
           "minimum": 0,
           "type": "number"
         },
         ...
         "instances": {
           "default": 1,
           "description": "Number of Marathon instances to run.",
           "minimum": 0,
           "type": "integer"
         },
         "mem": {
           "default": 1536,
           "description": "Memory (MB) to allocate to each Marathon instance.",
           "minimum": 512,
           "type": "number"
         }
       },
       ...
     }
   }
   

2. Create a JSON configuration file. You can choose any name, but you might want to choose a pattern like <package-name>-config.json. For example, marathon-config.json.

   nano marathon-config.json
   

3. Use the properties objects to build your JSON options file. For example, to change the number of Marathon CPU shares to 3 and memory allocation to 2048:

   {
     "service": {
       "cpus": 3.0, "mem": 2048.0
      }
   }
   

4. From the DC/OS CLI, install the DC/OS service with the custom options file specified:

   dcos package install --options=marathon-config.json marathon
   

For more information, see the dcos package command reference documentation.