Getting Unexpected logs after upgrading fluentd version from 1.16.5 to 1.17.0 [Q&A]

[anupg336]

What is a problem?

Hi,

After upgrading from Fluentd version 1.16.5 to 1.17.0, we started seeing unexpected logs in the fluentd. It seems these logs are related to the changes made in the /usr/sbin/fluentd file in Fluentd v1.17.0.

if RUBY_PLATFORM =~ /linux/
  prevent_duplicate_launch = system("systemctl", "is-active", "fluentd", out: IO::NULL)
  if prevent_duplicate_launch
    if ["-c", "--config", "--dry-run", "-h", "--help", "--show-plugin-config"].none? {|allowing_opt| ARGV.include? allowing_opt}
      puts("Error: Can't start duplicate Fluentd instance with the default config.")
      if ARGV.include?("-v")
        puts("To take the version, please use '--version', not '-v' ('--verbose').")
      end
      puts <<EOS
To start Fluentd, please do one of the following:
(Caution: Please be careful not to start multiple instances with the same config.)
- Stop the Fluentd service 'fluentd'.
- Specify the config path explicitly by '-c' ('--config').
EOS
      exit 2
    end
  end
end

After removing these changes from v1.17.0, the logs disappeared.

Could someone help explain why we are encountering these logs?

Thanks!

Describe the configuration of Fluentd

No response

Describe the logs of Fluentd

System has not been booted with systemd as init system (PID 1). Can't operate.
Failed to connect to bus: Host is down
System has not been booted with systemd as init system (PID 1). Can't operate.
Failed to connect to bus: Host is down

Environment

- Fluentd version: 1.17.0
- TD Agent version: 5.1.0-1
- Fluent Package version: 5.1.0-1
- Docker image (tag):
- Operating system: "Ubuntu 22.04.1 LTS"
- Kernel version: 5.15.153.1-microsoft-standard-WSL2