Learn to start, stop, enable and inspect systemd services from the command line. 15.11.2025 | reading time: 2 min On modern Linux systems systemctl is the primary tool to control systemd services; use it to start, stop, enable, inspect and troubleshoot daemons directly from the shell. Bring a service online Practical example: start a fictional web service and check its status with `systemctl`; try the commands below to see the sequence and expected output: ``` sudo systemctl start webapp.service sudo systemctl status webapp.service ``` Sample output: ``` ● webapp.service - Example Web Application Loaded: loaded (/etc/systemd/system/webapp.service; enabled) Active: active (running) since Thu 2025-11-13 10:12:34 UTC; 2s ago Main PID: 1234 (webapp) ``` Enable, disable, mask and reload Make a service start at boot or prevent it from running with `enable`, `disable` and `mask`; combine actions with `--now` for immediate effect and run `systemctl daemon-reload` after changing unit files; example commands: ``` sudo systemctl enable --now webapp.service sudo systemctl is-enabled webapp.service sudo systemctl mask some-other.service sudo systemctl daemon-reload ``` Inspect logs and units When a service misbehaves, follow the logs and get full unit details: use `journalctl -u` to stream logs, `systemctl status -l` for the unit journal excerpt and `systemctl list-units --type=service` to find failed or inactive services; example: ``` sudo journalctl -u webapp.service -f sudo systemctl status -l webapp.service sudo systemctl list-units --type=service --state=failed ``` Complementary tools systemctl plays well with other utilities: `journalctl` for logs and filtering, `systemd-analyze` to inspect boot timing, `systemd-cgls` to view control groups, and legacy wrappers like `service` or `init.d` shims on some distributions; use these to correlate logs, performance and process trees while troubleshooting. Next steps Start practicing by managing real units, editing simple unit files and reading unit metadata with `systemctl show`; then level up to orchestration and automation, and consider deepening the skills with certification preparation such as CompTIA Linux+ or LPIC-1 using intensive exam training at bitsandbytes.academy. Join Bits & Bytes Academy First class LINUX exam preparation. boot-process processes utilities troubleshooting scripting
