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Systemctl, process management/shaare/VSEluw

  • linux
  • linux

Basic System Info Commands

  • uptime → time, uptime, users, load average
  • hostname → current hostname
  • ip hostname → show IP & hostname
  • uname -a → current OS and kernel info
  • which command → path to a command
  • cal → calendar for current month/year

    • cal 2025 → full year
  • bc → basic calculator

System Monitoring

  • systemctl → interact with systemd system manager
  • ps → view current processes
  • top → dynamic view of process usage

Systemctl Usage

  • systemctl start|stop|status servicename.service → manage service state
  • systemctl enable servicename.service → start service at boot
  • systemctl restart|reload servicename → restart or reload service
  • systemctl list-units --all → list all units
  • To add a service:

    • Create a unit file in /etc/systemd/system/servicename.service

Process Management

  • Start a process in the background:

    • Ctrl + Z then jobs → suspend and background
    • bg → continue in background
    • fg → bring back to foreground
  • Run process detached from terminal:

    • nohup process & → keep running after logout
    • nohup process > /dev/null 2>&1 & → suppress all logs/output

Killing and Prioritizing

  • pkill name → kill process by name
  • nice → start process with a priority (range -20 to 19)

    • lower = higher priority
    • nice -20 top

Jobs Monitoring

  • jobs → list background/foreground job states
3 months ago Permalink
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