Ubuntu

Fluent Bit is distributed as the fluent-bit package and is available for long-term support releases of Ubuntu. The latest officially supported version is Noble Numbat (24.04).

The recommended secure deployment approach is to use the following instructions.

Server GPG key

Add the Fluent Bit server GPG key to your keyring to ensure you can get the correct signed packages.

Follow the official Debian wiki guidance.

sudo sh -c 'curl https://packages.fluentbit.io/fluentbit.key | gpg --dearmor > /usr/share/keyrings/fluentbit-keyring.gpg'

Update your sources lists

On Ubuntu, you need to add the Fluent Bit APT server entry to your sources lists. Ensure codename is set to your specific Ubuntu release name. For example, focal for Ubuntu 20.04.

codename=$(grep -oP '(?<=VERSION_CODENAME=).*' /etc/os-release 2>/dev/null || lsb_release -cs 2>/dev/null)

Update your source's list:

echo "deb [signed-by=/usr/share/keyrings/fluentbit-keyring.gpg] https://packages.fluentbit.io/ubuntu/$codename $codename main" | sudo tee /etc/apt/sources.list.d/fluent-bit.list

Update your repositories database

Update the apt database on your system:

sudo apt-get update

Fluent Bit recommends upgrading your system to avoid potential issues with expired certificates:

sudo apt-get upgrade

If you receive the error Certificate verification failed, check if the package ca-certificates is properly installed:

sudo apt-get install ca-certificates

Install Fluent Bit

1. Ensure your GPG key is up to date.

2. Use the following apt-get command to install the latest Fluent Bit:

   sudo apt-get install fluent-bit

3. Instruct systemd to enable the service:

   sudo systemctl start fluent-bit

If you do a status check, you should see a similar output like this:

$ systemctl status fluent-bit

● fluent-bit.service - Fluent Bit
   Loaded: loaded (/lib/systemd/system/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 (fluent-bit)
    Tasks: 1
   Memory: 656.0K
      CPU: 1.393s
   CGroup: /system.slice/fluent-bit.service
           └─6739 /opt/fluent-bit/bin/fluent-bit -c /etc/fluent-bit/fluent-bit.conf
...

The default configuration of fluent-bit is collecting metrics of CPU usage and sending the records to the standard output. You can see the outgoing data in your /var/log/syslog file.