Questions:

1. What is the purpose of the "chattr" command in Linux, and how does it work?

It changes the attributes of a file, making it read-only or executable.
It changes a user's password attributes, allowing them to log in remotely.
It manages kernel modules, allowing them to be loaded or unloaded.
It controls file attributes like immutability, append-only, and no-dump.

2. What is "SELinux" in Linux, and how does it enhance system security?

SELinux is a lightweight Linux distribution optimized for running on embedded systems.
SELinux is a graphical user interface for managing system settings.
SELinux is a set of kernel-level security enhancements that enforce mandatory access controls, restricting the actions that processes and users can perform on files and resources.
SELinux is a protocol used for secure communication between Linux servers.

3. What is the purpose of the "mount" command in Linux?

Start a new process
Display memory usage
Attach a filesystem to a directory
Show system uptime

4. Which file contains the DNS resolver configuration in Linux?

/etc/hosts
/etc/dns.conf
etc/resolv.conf
/etc/networks

5. Which runlevel is typically used for single-user mode in Linux?

Runlevel 0
Runlevel 1
Runlevel 3
Runlevel S