The systemctl command is a utility which is responsible for examining and controlling the systemd system and service manager. It is a collection of system management libraries, utilities and daemons which function as a successor to the System V init daemon.
Here at LinuxAPT, as part of our Server Management Services, we regularly help our Customers to solve Ubuntu related errors.
In this context, we shall look into starting, stopping, and restarting services in Ubuntu 20.04.
Services are background processes that run when the OS boots and end when it shuts down.
Systemd is System Management Daemon and it refers to all the libraries, packages, and utilities around daemon.
Before you get started on staring, stopping, or restarting your services, you need to know the ones that are available on your system.
You can see a list of all the services available on your system by using:
systemctl list-unit-files --type service –allThis will enable you to view the services.
The state of your services can be enabled, disabled, static, masked, or generated.
To view running services, use:
sudo systemctl | grep runningThe result of this command is a list of running services.
To do this, Use the command below to start a service:
systemctl start {service-name}
To do this, Use the command below to stop a service:
systemctl stop {service-name}
To do this, Use the command below to restart a service:
systemctl restart {service-name}To do this, Use the command below to view the status of a service:
systemctl status {service-name}Service is a high-level command that redirects on different binaries. It is less advanced compared to systemd and is a part of init.
Compared to system, the service commands are a lot simpler. To view all services use:
service --status-allYou will be able to view the services.
The way they are displayed is different. [ + ] means the services is enabled and [ – ] means disabled.
Use the command below to start a service:
service {service-name} start
Use the command below to stop a service:
service {service-name} stopUse the command below to restart a service:
service {service-name} restartUse the command below to view the status of a service:
service {service-name} statusThe init scripts for services are loaded in the directory /etc/init.d/. Init stands for initialization, it is a daemon process that starts when the computer starts and ends when it shuts down. If init does not start, no process starts and the system reaches the Kernel Panic stage. It has been replaced by systemd which reduces computational overhead.
Use the command below to start a service:
/etc/init.d/{service name} stopUse the command below to stop a service:
/etc/init.d/{service name} stopUse the command below to restart a service:
/etc/init.d/{service name} restartUse this command to view the status of a service:
/etc/init.d/{service name} statusThis article will guide you steps on how you stop, start, or restart a #service in #Ubuntu 20.04. service operates on the files in /etc/init. d and was used in conjunction with the old init system. #systemctl operates on the files in /lib/systemd . If there is a file for your service in /lib/systemd it will use that first and if not it will fall back to the file in /etc/init. To list all loaded services on your system (whether active; running, exited or failed, use the list-units subcommand and --type switch with a value of service. To Check running process in #Linux: 1. Open the #terminal #window on Linux. 2. For remote Linux server use the ssh command for log in purpose. 3. Type the ps aux command to see all running process in Linux. 4. Alternatively, you can issue the top command or htop command to view running process in Linux.
