systemd-client

The definitive Python library for systemd. Manage services, create units, read journals, analyze security, control resources, and monitor everything — from Python or the terminal.

Documentation: kalexnolasco.github.io/systemd-client

Features

Install

pip install systemd-client            # Core (zero deps)
pip install systemd-client[tui]       # + Interactive TUI (ratatui-py)
pip install systemd-client[dbus]      # + D-Bus backend (dasbus)
pip install systemd-client[all]       # Everything

Quick Start

Manage services

from systemd_client import SystemdClient

with SystemdClient() as client:
    # List all running services
    for unit in client.list_units(unit_type="service"):
        print(f"{unit.name}: {unit.active_state} ({unit.sub_state})")

    # Get detailed status
    status = client.status("my-app.service")
    print(f"PID: {status.main_pid}, Since: {status.active_enter_timestamp}")

    # Control services
    client.restart("my-app.service")
    client.restart_units(["app.service", "worker.service"])  # batch

    # Quick checks
    print(f"Active: {client.is_active('my-app.service')}")

Create services from Python

from systemd_client import ServiceBuilder, TimerBuilder, SystemdClient

# Build a .service file with a fluent API
unit = (ServiceBuilder("my-app")
    .description("My FastAPI Application")
    .exec_start("/usr/bin/python3 /opt/app/main.py")
    .working_directory("/opt/app")
    .user("appuser")
    .environment({"PORT": "8080", "ENV": "production"})
    .restart("on-failure")
    .restart_sec(5)
    .wanted_by("default.target")
    .build())

# Deploy in one step
with SystemdClient() as client:
    client.install(unit)
    client.enable("my-app.service")
    client.start("my-app.service")

# Create a timer (cron replacement)
timer = (TimerBuilder("backup")
    .description("Daily backup")
    .on_calendar("*-*-* 02:00:00")
    .persistent(True)
    .wanted_by("timers.target")
    .build())

Run transient units (systemd-run)

with SystemdClient() as client:
    # One-off command as a systemd service
    result = client.run("/usr/bin/python3 /opt/backup.py", name="backup-task")
    print(f"Running: {result.unit_name}")

    # Schedule a recurring timer
    client.run_on_calendar("daily", "/usr/bin/python3 /opt/cleanup.py")

    # With resource limits
    client.run("make -j8", properties={"MemoryMax": "2G", "CPUQuota": "50%"})

Monitor resources

with SystemdClient() as client:
    # Set cgroup limits
    client.set_property("my-app.service", {"MemoryMax": "512M", "CPUQuota": "25%"})

    # Check resource usage
    usage = client.get_resource_usage("my-app.service")
    print(f"CPU: {usage.cpu_usage_nsec / 1e9:.1f}s")
    print(f"Memory: {usage.memory_current / 1024**2:.0f}MB")

    # List timers
    for timer in client.list_timers():
        print(f"{timer.name}: {timer.time_left}")

Security analysis

with SystemdClient() as client:
    # What's slow at boot?
    for entry in client.analyze_blame()[:5]:
        print(f"{entry.time_us / 1e6:.3f}s  {entry.unit}")

    # Security audit (0 = hardened, 10 = exposed)
    sec = client.analyze_security("my-app.service")
    print(f"Exposure: {sec.exposure}/10.0")

    # Verify unit files before deploying
    errors = client.analyze_verify("my-app.service")

sd_notify — from your Python service

# In a Type=notify systemd service:
from systemd_client.notify import SystemdNotifier

notifier = SystemdNotifier()
notifier.ready()                       # Tell systemd we're up
notifier.status("Listening on :8080")  # Update status text
notifier.watchdog()                    # Keep-alive ping
notifier.stopping()                    # Graceful shutdown

Async API

import asyncio
from systemd_client import AsyncSystemdClient

async def main():
    async with AsyncSystemdClient() as client:
        # Concurrent health check
        services = ["app.service", "worker.service", "scheduler.service"]
        results = await asyncio.gather(
            *(client.is_active(svc) for svc in services)
        )
        for svc, active in zip(services, results):
            print(f"{svc}: {'UP' if active else 'DOWN'}")

asyncio.run(main())

System scope

from systemd_client import SystemdClient, SystemdScope

# Manage system-wide services (requires root)
with SystemdClient(scope=SystemdScope.SYSTEM) as client:
    units = client.list_units(unit_type="service")

CLI

# Unit management
systemd-client list --type service
systemd-client list-unit-files --state enabled
systemd-client status my-app.service
systemd-client cat my-app.service
systemd-client start my-app.service
systemd-client stop my-app.service
systemd-client restart a.service b.service c.service  # batch
systemd-client restart --no-block my-app.service
systemd-client try-restart my-app.service
systemd-client reload-or-restart my-app.service
systemd-client enable my-app.service
systemd-client reset-failed my-app.service
systemd-client kill my-app.service --signal SIGHUP

# Create and deploy unit files
systemd-client create-service --name my-app --exec-start /bin/app --restart on-failure --install
systemd-client create-timer --name backup --on-calendar daily --install
systemd-client install my-app.service --from-file ./my-app.service
systemd-client uninstall my-app.service

# Transient units (systemd-run)
systemd-client run /bin/echo hello --name my-task --wait
systemd-client run /opt/backup.py --on-calendar daily

# Resource monitoring
systemd-client resources my-app.service
systemd-client list-timers
systemd-client list-sockets
systemd-client list-dependencies my-app.service

# Analysis
systemd-client analyze-blame
systemd-client analyze-security my-app.service
systemd-client analyze-verify my-app.service

# Environment and sessions
systemd-client show-environment
systemd-client set-environment MY_VAR=hello
systemd-client list-sessions
systemd-client list-users

# Power management
systemd-client poweroff
systemd-client reboot
systemd-client suspend

# System scope
systemd-client --scope system list --type service
systemd-client --scope system restart nginx.service

# Interactive TUI dashboard
systemd-client tui
systemd-client --scope system tui

# Output formats
systemd-client --json list
systemd-client --no-color status my-app.service

Interactive TUI

Launch the full interactive dashboard:

systemd-client tui

Features:

• Real-time unit list with color-coded states (green=active, red=failed)
• Mouse support: click to select, scroll wheel, tab clicks
• Keyboard: s=start, S=stop, r=restart, e=enable, d=disable, j=journal
• Type filters: F1=All, F2=Services, F3=Timers, F4=Sockets, F5=Failed
• Search: / to filter by name
• Journal panel at bottom with auto-refresh
• Scope toggle with Tab, 3 tabs: Dashboard, Timers, Help
• Powered by Ratatui (Rust rendering engine, 30-60 FPS)

Requires: pip install systemd-client[tui]

Architecture

Your Application
    |
    +-- SystemdClient (sync)
    |       |
    +-- AsyncSystemdClient (async)
            |
            +-- SubprocessBackend ---- systemctl --user/--system ----> systemd
            |     (default, zero deps)
            +-- DBusBackend ---------- D-Bus session/system bus ----> systemd
            |     (optional, dasbus)
            +-- AsyncJournalReader --- journalctl --output=json -----> journal
            +-- Builders ------------- .service/.timer/.socket/.path -> unit files
            +-- Analyze -------------- systemd-analyze ----------------> boot/security
            +-- Notify --------------- $NOTIFY_SOCKET -----------------> sd_notify

Requirements

• Python >= 3.11
• Linux with systemd
• systemctl and journalctl on PATH

License

LGPL-2.1-or-later

systemd-client · Documentation · GitHub · PyPI