Linux System Installation & Configuration Flashcards

Which command creates a new ext4 filesystem on /dev/sdb1?

Answer: mkfs.ext4 /dev/sdb1

mkfs.ext4 is the standard command to create an ext4 filesystem; it is equivalent to mke2fs -t ext4.

A sysadmin needs to add a second disk to an existing LVM volume group. Which sequence is correct?

Answer: pvcreate → vgextend → lvextend

You must first initialize the disk as a physical volume (pvcreate), then add it to the volume group (vgextend), then optionally extend logical volumes (lvextend).

Which kernel parameter passed at boot disables SELinux for a single session?

Answer: selinux=0

Passing selinux=0 on the kernel command line completely disables SELinux for that boot session without permanently changing the policy configuration.

Which configuration file sets the DNS resolver search domain and nameserver addresses on a traditional (non-NetworkManager) Linux system?

Answer: /etc/resolv.conf

/etc/resolv.conf contains 'nameserver' and 'search' directives that configure the system's DNS resolver library.

What is the purpose of 'dracut' on Red Hat-based systems?

Answer: Generates the initramfs image

dracut is the tool used on Red Hat/Fedora systems to build the initramfs (initial RAM filesystem) image that the bootloader passes to the kernel.

Which command checks and reports the disk usage of a directory tree in human-readable format?

Answer: du -sh /home

'du -sh /home' summarizes the total disk usage of the /home directory tree in a human-readable format (KB, MB, GB).

Which /proc file contains the kernel's command line parameters as passed by the bootloader?

Answer: /proc/cmdline

/proc/cmdline contains the exact command line string that the bootloader passed to the kernel at boot time.