> ## 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.

# Install Core Agent on Linux (Debian-based)

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

In Chronosphere Telemetry Pipeline, you can use [fleets](/ingest/pipeline/v2/fleets) to manage instances
of Core Agent. Use this guide to install Core Agent on Debian-based Linux distributions.

## Supported environments

Core Agent supports the following Debian-based distributions and architectures:

| Distribution                   | Architectures   |
| ------------------------------ | --------------- |
| Debian 11 (Bullseye)           | x86-64, arm64v8 |
| Debian 10 (Buster)             | x86-64, arm64v8 |
| Ubuntu 22.04 (Jammy Jellyfish) | x86-64, arm64v8 |
| Ubuntu 20.04 (Focal Fossa)     | x86-64, arm64v8 |
| Ubuntu 18.04 (Bionic Beaver)   | x86-64, arm64v8 |
| Ubuntu 16.04 (Xenial Xerus)    | x86-64          |

## Dependencies

For Debian-based installations, Core Agent has the following general dependencies:

* libc
* libsasl
* libsystemd
* libyaml
* OpenSSL
* zlib

To retrieve a list of specific dependencies for your environment, run the following command:

```shell /PACKAGE/ theme={null}
dpkg -I PACKAGE
```

Replace *`PACKAGE`* with the name of the Core Agent package.

## Validate packages

When retrieving packages from the Core Agent repository, Chronosphere uses dual
validation (SHA256) and a GPG key.

### SHA256 check

The SHA256 file is distributed as the `files.sha256` file in the Core Agent repository.
This file contains a list of all included packages.

```shell theme={null}
shasum -a 256 calyptia-fluent-bit-X.<extension>
```

## Verify signatures

Core Agent packages are signed with `calyptia.key`. You can use dpkg and apt-key
to verify these signatures.

```shell theme={null}
apt-key add calyptia.key && \
dpkg-sig --list PACKAGE
```

Replace *`PACKAGE`* with the name of the Core Agent package.

## Install

Use these steps to install and enable Core Agent:

1. Run the following command to update your APT package list:

   ```shell theme={null}
   sudo apt-get update
   ```

2. Run the following command to upgrade your APT packages:

   ```shell theme={null}
   sudo apt-get upgrade
   ```

3. Run the following command to install Core Agent:

   ```shell theme={null}
   sudo apt-get install calyptia-fluent-bit
   ```

4. Run the following command to instruct systemd to enable the Core Agent service:

   ```shell theme={null}
   sudo systemctl calyptia-fluent-bit start
   ```

5. Perform a status check to confirm Core Agent is active. The status check
   should return output similar to the following:

   ```shell theme={null}
   sudo service calyptia-fluent-bit status
   ● calyptia-fluent-bit.service - Calyptia Fluent Bit
      Loaded: loaded (/lib/systemd/system/calyptia-fluent-bit.service; disabled; vendor preset: enabled)
      Active: active (running) since mié 2016-07-06 16:58:25 CST; 2h 45min ago
    Main PID: 6739 (calyptia-fluent-bit)
       Tasks: 1
      Memory: 656.0K
         CPU: 1.393s
      CGroup: /system.slice/calyptia-fluent-bit.service
              └─6739 /opt/calyptia-fluent-bit/bin/calyptia-fluent-bit -c /etc/calyptia-fluent-bit/calyptia-fluent-bit.conf
   ```

   The default configuration of Core Agent is to collect metrics of CPU usage
   and send those metrics to stdout. You can see this outgoing data in your
   `/var/log/messages` file.