Linux essential commands for service and process management in hindi скачать в хорошем качестве

Linux essential commands for service and process management in hindi

ps command to List Processes "ps" command is the most basic command to see all the running processes on the system. It outputs all running processes of specific user or all users. To see running processes of existing user: ps The output will be similar to this: PID TTY TIME CMD 81775 pts/0 00:00:00 bash 90379 pts/0 00:00:00 ps To see running processes of all users: ps -aux To view specific service/user running processes: ps -ef | grep httpd ​ pstree command in Linux “pstree” command will be useful if you want to see running processes hierarchically arranged in tree format. It’s easy to understand parent and child processes using this command. It is used as a more visual alternative to the ps command. The root of the tree is either init or the process with the given pid. nice command to change process priorities nice command is used to assign particular priority, thus giving the process more or less CPU time than other processes. Process priority values range from -20 to 19. Lower the nice value, higher the priority. The default nice value is 0. It means -20 has highest priority over 15. I kill command Every process in Linux responds to signals. Signals are commands or instructions to processes to terminate or modify their behavior. The default way to send signals to processes is through Kill command. The very common kill command syntax are: kill pid This sends the TERM signal to the process. The TERM signal tells the process to please terminate. This allows the program to perform clean-up operations and exit smoothly. systemctl. Without any argument, it runs the systemctl list-units command, which outputs a list of the active units. If you run systemctl status, the output shows a hierarchical overview of the running services. Comparing both outputs, you immediately see that there are multiple kinds of units and that services are only one among them. Each service is represented by a service unit, which is described by a service file usually shipped in /lib/systemd/system/ (or /run/systemd/system/, or /etc/systemd/system/; they are listed by increasing order of importance, and the last one wins). Each is possibly modified by other service-name.service.d/*.conf files in the same set of directories. Those unit files are plain text files whose format is inspired by the well-known “*.ini” files of Microsoft Windows, with key = value pairs grouped between [section] headers. Here we see a sample service file for /lib/systemd/system/ssh.service: