Kategorie: Allgemein

Trap The trap command is a shell built-in that allows you to catch and handle signals sent to your shell session. A signal is a notification from the operating system to the shell or running programs, typically indicating something has gone wrong or needs attention. What’s it for? You might use trap in situations where:…

Virsh virsh is a powerful command-line tool for managing virtual machines (VMs) created with libvirt, a popular open-source virtualization platform. With virsh, you can perform various tasks such as creating, editing, deleting, and monitoring VMs, as well as managing storage and network resources. Use cases: Create new VMs from scratch or clone existing ones Edit…

cgroups Cgroups, short for Control Groups, is a Linux kernel feature that allows you to limit, measure, and prioritize resources such as CPU time, memory, disk I/O, and network bandwidth. This feature was introduced with Linux 2.6.24 and has been extensively used in containerization (e.g., Docker) and cloud computing environments. What’s the use of cgroups?…

sar The sar command is a powerful tool for monitoring system performance and resource utilization on Linux systems. It stands for „System Activity Reporter“ and provides detailed statistics about various system metrics such as CPU, memory, disk I/O, network activity, and more. Use Cases: Monitoring system load and usage over time to identify bottlenecks or…

Tar The tar command is a powerful tool used to create and manage archives of files on Linux systems. It stands for Tape Archive, but it’s not limited to archiving data to tape media anymore. With tar, you can package multiple files into one single file, compress them, and even extract archives from various formats.…

du The du command stands for „disk usage“ and is used to estimate the disk space occupied by files and directories on a Linux system. It’s a versatile tool that can be used by beginners, intermediate users, and even professionals. What is it used for? Checking file sizes: du displays the total size of each…

df The df command is a built-in Linux utility that displays information about the file system disk space usage. It shows the total amount of used, available, and percentage of space used on each file system mounted on your system. Use cases: Checking the disk space usage on a specific file system (e.g., /, /home,…

Top The top command is a system monitoring tool that provides real-time information about the system’s processes, memory usage, CPU load, and other vital statistics. It’s a powerful and essential tool for any Linux user to understand the current state of their system. What does it do? When you run top, it displays a dynamic…

ps The ps command, short for „process status“, is used to display information about currently running processes on your system. This includes details such as process IDs, user accounts associated with them, CPU usage, memory consumption, and more. Basic Use Case You can use the ps command in various forms, depending on your needs. Here…

grep The grep command is a powerful tool used to search for specific text patterns within one or more files. It stands for „Global Regular Expression Print“, which aptly describes its functionality. With grep, you can quickly scan through text data, whether it’s in log files, source code, or documentation. Use Cases Searching Log Files:…