What is the Linux Systemctl Command?

What is Systemd?

Systemd is like the traffic manager for your Linux system. It’s a modern tool that organizes and supervises how different parts of your system start and run. Imagine it as a smarter, faster way to handle tasks compared to older methods. Instead of doing things one after the other, systemd can get multiple tasks going at the same time, making your computer start up quicker and respond faster. It uses something called “units” to keep everything in order – like services, sockets, and devices – helping your system run smoothly....

What is the Linux Systemctl Command?

Now, imagine you have a remote control for your Linux system – that’s what `systemctl` is. It’s like your boss for telling the system what to do. With this tool, you can start, stop, or restart services (think of them like programs running in the background). Want something to start automatically when your computer turns on? `systemctl` helps with that too. It’s also good for checking how things are going – like looking at logs or figuring out what other things a service needs to work properly. So, if you’re in charge of a Linux system, `systemctl` is your go-to tool for keeping things organized and running well....

Syntax of `systemctl` command in Unix

systemctl [command] [service]...

How to Manage System Services in Linux

1) Starting and Stopping Services...

Options available in `systemctl` command in Unix

Options                                                      Description Syntax –version This option displays the version number of the systemctl command. systemctl --version –help This option displays the help manual for systemctl, including a list of available options and commands systemctl --help –type The argument in this case should be comma-separated list of unit types such as service and socket. systemctl --type=service –all This option lists all available units, including those that are inactive. systemctl --all –failed This option lists all units that have failed.  systemctl --failed –user talk to service manager of calling user, instead of system. systemctl --user –force This option forces the service to start or stop, even if it has dependencies that are not yet started or stopped. systemctl stop --force httpd.service –no-block This option starts or stops the service without blocking the shell, allowing the user to continue to use the shell while the service is starting or stopping. systemctl start --no-block httpd.service –state This option is used to filter the output based on the specified unit state. You can specify one or more-unit states separated by commas, such as active, inactive, failed, and activating.  For example: to list all the failed units. systemctl list-units --state=failed -r, –recursive This option is used to show units of local containers as well.  For example: to list all units including those in local containers. systemctl list-units --recursive –show-types This option is used to show the types of sockets along with showing sockets.  For example: to show the types of all sockets. systemctl list-sockets --show-types –job-mode= This option controls how to deal with already queued jobs in case of queuing a new job. There are three available modes: replace: replace already queued jobs with the new one.fail: cancel the new job and return failure if there are already queued jobs.isolate: queue the new job and isolate it from the other jobs. For example: to use the replace mode. systemctl isolate graphical.target --job-mode=replace -i, –ignore-inhibitors This option is used to ignore inhibitor locks when requesting a system shutdown or sleep state.  For example: to ignore inhibitor locks when requesting a system shutdown. systemctl poweroff --ignore-inhibitors -q, –quiet This option is used to suppress the printing of results of various commands and the hints about the truncated lines.  For example: to reload the systemctl daemon without showing any output. systemctl daemon-reload --quiet –no-wall This option is used to not send a wall message before power-off, halt, or reboot.  For example: to halt the system without sending a wall message. systemctl halt --no-wall...

Frequently Asked Questions

1. What is the role of systemd in Linux, and how does it differ from traditional init systems?...

Conclusion

In this article we will understand the use of `systemctl` command in Linux and How to manage system services in linux. By mastering systemctl, you gain full control over your system’s services, ensuring optimal performance and stability. Whether you’re a seasoned Linux admin or just starting, this powerful command is a valuable tool in your arsenal. So, dive in, explore its capabilities, and take command of your Linux system!...