Systemd and systemctl are two terms often encountered when working with Linux systems. Many of new Linux user get confused? While they may seem similar, they refer to different components in the Linux ecosystem.
This article will provide a detailed explanation of the differences between systemd and the systemctl command, exploring their roles and functionalities in Linux system management.
What is Systemd?
Systemd is an init system used in Linux distributions to bootstrap user space components and manage system processes. It was designed to overcome the limitations of traditional init systems, such as SysV and Upstart, and to simplify the process of managing system services.
The key features of systemd include:
- Parallelization: Systemd can start multiple services simultaneously, reducing boot time and improving system performance.
- Dependency management: Systemd manages service dependencies automatically, ensuring that required services are started in the correct order.
- Logging: Systemd incorporates the journald logging system, which collects and stores logs for all system components, making it easier to troubleshoot issues.
- Cgroups integration: Systemd uses Control Groups (cgroups) to track and manage processes, enhancing resource management and process isolation.
- Configuration files: Systemd uses unit files, which are simple text files, to define and configure services, making it easier to manage and customize system components.
What is Systemctl?
The systemctl command is a command-line utility that interacts with the systemd system and service manager. It is the primary tool used to control and manage systemd services, allowing users to start, stop, enable, disable, and check the status of services.
Some common systemctl commands include:
- Start a service:- systemctl start SERVICE_NAME
- Stop a service:- systemctl stop SERVICE_NAME
- Restart a service:- systemctl restart SERVICE_NAME
- Enable a service to start at boot:- systemctl enable SERVICE_NAME
- Disable a service from starting at boot:- systemctl disable SERVICE_NAME
- Check the status of a service:- systemctl status SERVICE_NAME
- List all running services:- systemctl list-units –type=service
Difference Between Systemd and Systemctl
Systemd is the init system and service manager responsible for managing system processes, while systemctl is the command-line interface used to interact with and control systemd. In summary:
- Systemd is the underlying system that manages services, processes, and resources.
- Systemctl is a command-line tool used to interact with and control systemd services and components.
Understanding the differences between systemd and the systemctl command is crucial for managing Linux systems efficiently. While systemd is the system and service manager responsible for bootstrapping and managing processes, systemctl serves as the command-line interface used to control and interact with systemd services.
By mastering both components, users can efficiently manage and maintain their Linux systems.