# Redhat / CentOS

Fluent Bit is distributed as the `fluent-bit` package and is available for the latest stable CentOS system.

Fluent Bit supports the following architectures:

* `x86_64`
* `aarch64`
* `arm64v8`

For CentOS 9 and later, Fluent Bit uses [CentOS Stream](https://www.centos.org/centos-stream/) as the canonical base system.

## Single line install

Fluent Bit provides an installation script to use for most Linux targets. This will always install the most recently released version.

```bash
curl https://raw.githubusercontent.com/fluent/fluent-bit/master/install.sh | sh
```

This is a convenience helper and should always be validated prior to use. The recommended secure deployment approach is to use the following instructions:

## CentOS 8

CentOS 8 is now end-of-life, so the default Yum repositories are unavailable.

Ensure you've configured an appropriate mirror. For example:

```shell
sed -i 's/mirrorlist/#mirrorlist/g' /etc/yum.repos.d/CentOS-* && \
sed -i 's|#baseurl=http://mirror.centos.org|baseurl=http://vault.centos.org|g' /etc/yum.repos.d/CentOS-*
```

An alternative is to use Rocky or Alma Linux, which should be equivalent.

## Configure Yum

The `fluent-bit` is provided through a Yum repository. To add the repository reference to your system:

1. In `/etc/yum.repos.d/`, add a new file called `fluent-bit.repo`.
2. Add the following content to the file:

   ```
   [fluent-bit]
   name = Fluent Bit
   baseurl = https://packages.fluentbit.io/centos/$releasever/
   gpgcheck=1
   gpgkey=https://packages.fluentbit.io/fluentbit.key
   repo_gpgcheck=1
   enabled=1
   ```
3. As a best practice, enable `gpgcheck` and `repo_gpgcheck` for security reasons. Fluent Bit signs its repository metadata and all Fluent Bit packages.

### Updated key from March 2022

For the 1.9.0 and 1.8.15 and later releases, the [GPG key has been updated](https://packages.fluentbit.io/fluentbit.key). Ensure this new one is added.

The GPG Key fingerprint of the new key is:

```
C3C0 A285 34B9 293E AF51  FABD 9F9D DC08 3888 C1CD
Fluentbit releases (Releases signing key) <releases@fluentbit.io>
```

The previous key is [still available](https://packages.fluentbit.io/fluentbit-legacy.key) and might be required to install previous versions.

The GPG Key fingerprint of the old key is:

```
F209 D876 2A60 CD49 E680 633B 4FF8 368B 6EA0 722A
```

Refer to the [supported platform documentation](https://docs.fluentbit.io/manual/3.2/installation/supported-platforms) to see which platforms are supported in each release.

### Install

1. After your repository is configured, run the following command to install it:

   ```bash
   sudo yum install fluent-bit
   ```
2. Instruct `Systemd` to enable the service:

   ```bash
   sudo systemctl start fluent-bit
   ```

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

```bash
$ systemctl status fluent-bit
● fluent-bit.service - Fluent Bit
   Loaded: loaded (/usr/lib/systemd/system/fluent-bit.service; disabled; vendor preset: disabled)
   Active: active (running) since Thu 2016-07-07 02:08:01 BST; 9s ago
 Main PID: 3820 (fluent-bit)
   CGroup: /system.slice/fluent-bit.service
           └─3820 /opt/fluent-bit/bin/fluent-bit -c etc/fluent-bit/fluent-bit.conf
...
```

The default Fluent Bit configuration collect metrics of CPU usage and sends the records to the standard output. You can see the outgoing data in your `/var/log/messages` file.

## FAQ

### Yum install fails with a "404 - Page not found" error for the package mirror

The `fluent-bit.repo` file for the latest installations of Fluent Bit uses a `$releasever` variable to determine the correct version of the package to install to your system:

```
[fluent-bit]
name = Fluent Bit
baseurl = https://packages.fluentbit.io/centos/$releasever/$basearch/
...
```

Depending on your Red Hat distribution version, this variable can return a value other than the OS major release version (for example, RHEL7 Server distributions return `7Server` instead of `7`). The Fluent Bit package URL uses the major OS release version, so any other value here will cause a 404.

To resolve this issue, replace the `$releasever` variable with your system's OS major release version. For example:

```
[fluent-bit]
name = Fluent Bit
baseurl = https://packages.fluentbit.io/centos/7/$basearch/
gpgcheck=1
gpgkey=https://packages.fluentbit.io/fluentbit.key
repo_gpgcheck=1
enabled=1
```