LFCS Certification Firewall and Packet Filtering 4

Question 1

Which file is commonly used to persist iptables rules on RHEL/CentOS systems?

Accepted Answer

/etc/sysconfig/iptables

Answer

On RHEL/CentOS systems, iptables rules are saved to /etc/sysconfig/iptables and loaded at boot by the iptables service.

Question 2

What does the iptables '-j RETURN' target do when used inside a user-defined chain?

Accepted Answer

Stops processing and returns to the calling chain

Answer

RETURN causes the packet to stop traversing the current chain and resume processing in the calling (parent) chain.

Question 3

Which firewalld feature allows grouping multiple IP addresses or ranges for use in rules?

Accepted Answer

ipsets

Answer

Firewalld supports ipsets, which allow efficient matching against large sets of IP addresses or networks.

Question 4

In nftables, what keyword is used to specify the hook and priority when creating a chain?

Accepted Answer

type ... hook ... priority

Answer

An nftables base chain is defined with 'type hook priority ' to attach it to the netfilter framework.

Question 5

What iptables command saves current rules to a file for later restoration?

Accepted Answer

iptables-save > file

Answer

The 'iptables-save' command outputs all current iptables rules in a format suitable for restoration with iptables-restore.

LFCS Certification Practice Test