anchor.diff:  sudo journalctl -f -u buildkite-agent@2
   ```
   
  -For older systems without `systemd` (such as Amazon Linux) you instead use:
  -
  -```shell
  -sudo cp /etc/init.d/buildkite-agent /etc/init.d/buildkite-agent-2
  -sudo chkconfig --add buildkite-agent-2
  -sudo service buildkite-agent-2 start
  -```
  -
   ## Upgrading
   
   ```shell
  
positive.code: # Installing Buildkite Agent on Red Hat, CentOS and Amazon Linux
  
  The Buildkite Agent can be installed on Red Hat, CentOS and Amazon Linux using our yum repository.
  
  {:toc}
  
  
negative.code: And then start the agent, and tail the logs:
  
  ```shell
  sudo systemctl enable buildkite-agent && sudo systemctl start buildkite-agent
  sudo tail -f /var/log/messages
  ```
  
  ## SSH Key Configuration
  