Create and manage systemd services and timers. Configure service dependencies and resource limits. Use when managing system services.

Systemd Services Create, manage, and monitor systemd services and timers. Covers unit file authoring, dependency management, socket activation, resource limits, journalctl log analysis, and production hardening. When to Use Deploying an application as a managed background service Replacing cron jobs with systemd timers for better logging and dependency control Setting up socket activation for on demand service startup Configuring resource limits (CPU, memory, I/O) for services Debugging service startup failures and runtime crashes Managing service dependencies and ordering Prerequisites Linux system running systemd (most modern distributions) Root or sudo access for creating system level unit files Application binary or script to run as a service Understanding of the application's start/stop lifecycle Service Unit File Complete Example Service Management Commands Timer Units (Cron Replacement) Timer File Corresponding Service File Timer Management Socket Activation Dependency Management Resource Limits (cgroups v2) Journalctl Log Analysis Troubleshooting Symptom Diagnostic Command Common Fix Service fails to start systemctl status myapp , journalctl u myapp n 50 Check ExecStart path, permissions, config syntax Service keeps restarting journalctl u myapp since "5 min ago" Check StartLimitBurst; look for crash in logs "Main process exited, code=exited, status=217" journalctl u myapp User or group in unit file does not exist "Failed to set up mount namespacing" Check ProtectSystem/PrivateTmp Kernel too old or SELinux blocking; relax directives Timer not firing systemctl list timers , systemctl status backup.timer Ensure timer is enabled; validate OnCalendar expression Service starts before dependency Check After= and Requires= Add After=dependency.service for ordering OOM killed journalctl k \ grep oom , dmesg Increase MemoryMax or optimize application memory Cannot bind to port 80 Check AmbientCapabilities Add CAP NET BIND SERVICE or use a higher port Related Skills linux administration General system administration context performance tuning Kernel tuning and resource optimization user management Service accounts and permissions backup recovery Scheduling backups with systemd timers

systemd-services