Linux System Administration 4

Question 1

What is the purpose of the `/etc/hosts.allow` and `/etc/hosts.deny` files?

Accepted Answer

Define TCP Wrappers access control rules

Answer

TCP Wrappers reads `/etc/hosts.allow` and `/etc/hosts.deny` to permit or block connections to wrapped services.

Question 2

Which command would display all open network ports and the processes listening on them?

Accepted Answer

netstat -tulpn

Answer

`netstat -tulpn` shows TCP/UDP listening ports with the process name/PID (requires root for all processes).

Question 3

You want to find all files modified in the last 24 hours under `/var/log`. Which command is correct?

Accepted Answer

find /var/log -mtime -1

Answer

`-mtime -1` matches files modified less than 1 day (24 hours) ago; the minus sign means 'less than'.

Question 4

What is the primary function of `logrotate`?

Accepted Answer

Manages automatic rotation, compression, and deletion of log files

Answer

`logrotate` automatically rotates, compresses, removes, and mails log files based on rules in `/etc/logrotate.conf`.

Question 5

Which `iptables` chain filters packets destined for the local system?

Accepted Answer

INPUT

Answer

The INPUT chain processes packets destined for the local machine's own network stack.

Linux Practice Test