RHCSA EX200 Flashcards

Which command adds a swap partition at /dev/sdb2 and activates it immediately without a reboot?

Answer: mkswap /dev/sdb2 && swapon /dev/sdb2

mkswap formats the partition as swap space, and swapon activates it immediately for use by the kernel.

Which configuration file defines system-wide resource limits (e.g., max open files) for PAM-authenticated sessions?

Answer: /etc/security/limits.conf

/etc/security/limits.conf sets per-user and per-group limits enforced by the pam_limits module at login.

You need to redirect all port 80 traffic to port 8080 on the local machine using firewalld. Which command does this?

Answer: firewall-cmd --add-forward-port=port=80:proto=tcp:toport=8080 --permanent

The --add-forward-port option in firewalld handles local port redirection; --permanent makes it survive reboots.

Which command lists all active and inactive systemd unit files along with their enabled/disabled state?

Answer: systemctl list-unit-files

'systemctl list-unit-files' shows all installed unit files and whether they are enabled, disabled, or static.

When configuring autofs to automount an NFS share, which file defines the mount point directory and points to the map file?

Answer: /etc/auto.master

/etc/auto.master (or /etc/auto.master.d/) is the master map that links mount point directories to their indirect or direct map files.

A script requires JAVA_HOME to be set for all users at login. Which file is the best place to define this environment variable system-wide?

Answer: /etc/profile.d/java.sh

Files in /etc/profile.d/ with a .sh extension are sourced for all users during login, making it the standard place for system-wide environment variables.

Which command verifies that a container image will run correctly as a systemd service by checking the generated unit file before enabling it?

Answer: podman generate systemd --name container_name

'podman generate systemd --name' outputs the unit file content to stdout so you can review it before placing it in the systemd directory.