> ## Documentation Index
> Fetch the complete documentation index at: https://docs.chronosphere.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Add agents to a fleet

<Note>
  This feature isn't available to all Chronosphere Telemetry Pipeline users.
  For more information, contact [Chronosphere Support](/support).
</Note>

After you've [created a fleet](/ingest/pipeline/v2/fleets#create-a-fleet), you can add
[supported telemetry agents](/ingest/pipeline/v2/fleets/agent) to that fleet.

<Warning>
  When an agent joins a fleet, that agent's standalone configuration file is
  replaced by the configuration file that governs the entire fleet. Any settings previously
  configured in the standalone configuration file but not
  in the fleet-level configuration file will be permanently overwritten.

  Certain settings in an agent's standalone configuration file are necessary part
  of the agent creation process, and can later be overwritten by fleet-level
  settings without issue. However, any text in the original standalone configuration
  file is lost forever, so be sure to save critical key/value information in a separate
  location, or [update the fleet-level configuration file](/ingest/pipeline/v2/fleets#update-a-fleet) accordingly.
</Warning>

## Add a Fluent Bit agent

> Requires Fluent Bit v2.1.8 or later.

To add a Fluent Bit agent to a fleet:

<Tabs>
  <Tab title="YAML configuration" id="fluent-yaml">
    <Note>
      YAML configuration is only supported in Chronosphere Telemetry Pipeline v2.25.0
      or later, and requires Fluent Bit v3.2 or later. Additionally, to use YAML
      configuration files for individual agents in a fleet, the `fleet_config_legacy_format`
      parameter in that fleet's configuration file must be set to `false`.
    </Note>

    1. If necessary, [install a new Fluent Bit agent](https://docs.fluentbit.io/manual/installation/getting-started-with-fluent-bit).

    2. Update the `customs` section in the configuration file for that agent.

       ```yaml theme={null}
       customs:
         - name: calyptia
           calyptia_host: HOST
           api_key: 'KEY'
           fleet_name: 'NAME'
           fleet.interval_sec: SECONDS
           fleet.interval_nsec: NANOSECONDS
           fleet_config_legacy_format: false
       ```

       Replace the following values:

       * *`HOST`*: Your Chronosphere hostname. If you don't know your hostname, ask
         a Chronosphere representative for this value.
       * *`KEY`*: The [API token](/ingest/pipeline/pipeline-cli/authenticate) you use to
         authenticate with Telemetry Pipeline.
       * *`NAME`*: The name of the fleet to which your agent will be added.
       * *`SECONDS`*: How often, in seconds, this agent should check for configuration
         updates. If unspecified, defaults to `15`.
       * *`NANOSECONDS`*: How often, in nanoseconds, this agent should check for
         configuration updates. If unspecified, defaults to `0`.

    3. Run the following command:

       ```shell theme={null}
       fluent-bit -c CONFIG
       ```

       Replace *`CONFIG`* with the name of the configuration file you updated in the
       previous step.
  </Tab>

  <Tab title="Classic configuration" id="fluent-classic">
    1. If necessary, [install a new Fluent Bit agent](https://docs.fluentbit.io/manual/installation/getting-started-with-fluent-bit).

    2. Update the `[CUSTOM]` section in the configuration file for that agent.

       ```shell theme={null}
       [CUSTOM]
           Name calyptia
           Calyptia_Host HOST
           API_Key KEY
           Fleet_Name NAME
           fleet.interval_sec SECONDS
           fleet.interval_nsec NANOSECONDS
       ```

       Replace the following values:

       * *`HOST`*: Your Chronosphere hostname. If you don't know your hostname, ask
         a Chronosphere representative for this value.
       * *`KEY`*: The [API token](/ingest/pipeline/pipeline-cli/authenticate) you use to
         authenticate with Telemetry Pipeline.
       * *`NAME`*: The name of the fleet to which your agent will be added.
       * *`SECONDS`*: How often, in seconds, this agent should check for configuration
         updates. If unspecified, defaults to `15`.
       * *`NANOSECONDS`*: How often, in nanoseconds, this agent should check for
         configuration updates. If unspecified, defaults to `0`.

    3. Run the following command:

       ```shell theme={null}
       fluent-bit -c CONFIG
       ```

       Replace *`CONFIG`* with the name of the configuration file you updated in the
       previous step.
  </Tab>
</Tabs>

## Add a Core Agent

> Requires Core Agent v23.4.5 or later.

To add an instance of Core Agent to a fleet:

<Tabs>
  <Tab title="YAML configuration" id="agent-yaml">
    <Note>
      YAML configuration is only supported in Chronosphere Telemetry Pipeline v2.25.0 or later,
      and requires Core Agent v25.1.1 or later. Additionally, to use YAML
      configuration files for individual agents in a fleet, the `fleet_config_legacy_format`
      parameter in that fleet's configuration file must be set to `false`.
    </Note>

    1. If necessary, [install a new instance of Core Agent](https://docs.calyptia.com/calyptia-for-fluent-bit/installation/getting-started-with-fluent-bit).

    2. Update the `customs` section in the configuration file for that agent.

       ```yaml theme={null}
       customs:
         - name: calyptia
           calyptia_host: HOST
           api_key: 'KEY'
           fleet_name: 'NAME'
           fleet.interval_sec: SECONDS
           fleet.interval_nsec: NANOSECONDS
           fleet_config_legacy_format: false
       ```

       Replace the following values:

       * *`HOST`*: Your Chronosphere hostname. If you don't know your hostname, ask
         a Chronosphere representative for this value.
       * *`KEY`*: The [API token](/ingest/pipeline/pipeline-cli/authenticate) you use to
         authenticate with Telemetry Pipeline.
       * *`NAME`*: The name of the fleet to which your agent will be added.
       * *`SECONDS`*: How often, in seconds, this agent should check for configuration
         updates. If unspecified, defaults to `15`.
       * *`NANOSECONDS`*: How often, in nanoseconds, this agent should check for
         configuration updates. If unspecified, defaults to `0`.

    3. Run the following command:

       ```shell theme={null}
       calyptia-fluent-bit -c CONFIG
       ```

       Replace *`CONFIG`* with the name of the configuration file you updated in the
       previous step.
  </Tab>

  <Tab title="Classic configuration" id="agent-classic">
    1. If necessary, [install a new instance of Core Agent](https://docs.calyptia.com/calyptia-for-fluent-bit/installation/getting-started-with-fluent-bit).

    2. Update the `[CUSTOM]` section in the configuration file for that agent.

       ```shell theme={null}
       [CUSTOM]
           Name calyptia
           Calyptia_Host HOST
           API_Key KEY
           Fleet_Name NAME
           fleet.interval_sec SECONDS
           fleet.interval_nsec NANOSECONDS
       ```

       Replace the following values:

       * *`HOST`*: Your Chronosphere hostname. If you don't know your hostname, ask
         a Chronosphere representative for this value.
       * *`KEY`*: The [API token](/ingest/pipeline/pipeline-cli/authenticate) you use to
         authenticate with Telemetry Pipeline.
       * *`NAME`*: The name of the fleet to which your agent will be added.
       * *`SECONDS`*: How often, in seconds, this agent should check for configuration
         updates. If unspecified, defaults to `15`.
       * *`NANOSECONDS`*: How often, in nanoseconds, this agent should check for
         configuration updates. If unspecified, defaults to `0`.

    3. Run the following command:

       ```shell theme={null}
       calyptia-fluent-bit -c CONFIG
       ```

       Replace *`CONFIG`* with the name of the configuration file you updated in the
       previous step.
  </Tab>
</Tabs>