Can you list the main commands used by a Linux administrator to manage the system?

Main Linux commands frequently used by administrators for system management:

• top or htop — process and system load monitoring.
• ps — viewing running processes.
• kill, killall — terminating processes.
• systemctl — managing system services (start, stop, restart).
• journalctl — viewing system logs.
• df — information about free disk space.
• du — size of files and folders.
• mount / umount — mounting and unmounting filesystems.
• useradd, usermod, passwd — user management.
• chmod, chown — changing file permissions and ownership.
• iptables or firewalld — firewall configuration.
• ssh — remote server access.
• tar, gzip — archiving and compressing files.
• apt, yum, dnf — package management (depends on distribution).

These commands cover basic tasks related to monitoring, process management, users, files, and services.