Marcos is studying for his RHCE exam. Please generate and explain examples and commands to help him to master this objective: Operate running systems.
Certainly! Operating running systems is a key objective in the RHCE (Red Hat Certified Engineer) exam. Let's explore some examples and commands to help Marcos master this objective.
- Process Management:
Example: Checking running processes and their resource utilization using the
topcommand provides real-time information about system processes, CPU usage, memory usage, and other system statistics. It allows you to monitor and manage processes interactively.
Example: Terminating a running process using the
killcommand sends a signal to a process specified by its process ID (PID) to terminate it. The default signal sent is SIGTERM, but you can specify a different signal if needed.
- System and Service Management:
Example: Starting, stopping, and restarting a service using the
sudo systemctl start <service-name>
sudo systemctl stop <service-name>
sudo systemctl restart <service-name>
systemctlcommand is used to manage system services. These commands start, stop, or restart a service specified by its service name. You may need to run the commands with superuser privileges (
Example: Enabling a service to start at boot using the
sudo systemctl enable <service-name>
enableoption configures a service to start automatically at system boot. This ensures that the service starts up after a reboot or system restart.
- Network Configuration:
Example: Configuring network interfaces using the
nmcli connection modify <interface-name> ipv4.method manual ipv4.addresses <IP>/<subnet>
nmcli connection up <interface-name>
nmclicommand-line tool allows you to manage network connections. The first command configures a network interface with a static IPv4 address. The second command brings up the specified network interface.
Example: Displaying network configuration using the
ip address show
ip route show
ipcommand provides information about network interfaces, IP addresses assigned to them, and routing tables. The
address showsubcommand displays IP address details, while the
route showsubcommand shows the system's routing table.
These examples cover some essential commands for operating running systems, including process management, system and service management, and network configuration. By practicing these commands and understanding their usage, Marcos can effectively operate and manage Linux systems during his RHCE exam.