Linux VPN Server Configuration Quiz

1. In Linux VPN configuration, what does NAT masquerading accomplish?

Encrypts all traffic

Translates private VPN addresses to server addresses for internet access

Authenticates user credentials

Compresses data packets

2. Which command tests VPN connectivity from a Linux client to verify the tunnel is operational?

Ping through the VPN interface

Openvpn --test-config

Vpn-status

Tunnel-check

3. What does the 'verb' parameter control in an OpenVPN configuration?

Verbosity level for logging

Verification of certificates

Virtual bridge settings

Version requirements

4. Which encryption key size is considered secure for AES in modern VPN deployments?

64-bit

128-bit

256-bit

512-bit

5. What command pushes DNS settings to connected VPN clients in OpenVPN?

Push "dhcp-option DNS"

Dns-push

Set-dns

Route-dns

6. Which log file typically records OpenVPN server events and errors on Linux?

/var/log/openvpn.log

/var/log/syslog or /var/log/messages

/etc/openvpn/logs

/tmp/vpn.log

7. In IPSec, what does the 'tunnel mode' do differently than 'transport mode'?

Tunnel mode encrypts only the payload; transport mode encrypts the entire packet

Tunnel mode encrypts the entire packet; transport mode encrypts only payload

Tunnel mode is for UDP only

Transport mode requires additional hardware

8. Which utility is used to view real-time VPN connection statistics on Linux?

Netstat or ss

Ifconfig

Ping

Traceroute

9. What is the standard port used by OpenVPN if not explicitly configured?

443

1194

500

1723

10. Which daemon process manages OpenVPN on Linux systems?

Openvpnd

Openvpn (via systemd or init)

Vpnmanager

Netd

11. Which VPN protocol uses UDP port 500 and 4500 for key exchange and encrypted traffic?

IPSec

OpenVPN

L2TP

PPTP

12. Which VPN protocol is known for being lightweight and modern, using elliptic-curve cryptography?

PPTP

L2TP

WireGuard

SSTP

13. What is the purpose of the 'dh' parameter in OpenVPN server configuration?

Specifies DHCP settings

Defines Diffie-Hellman parameters for key exchange

Sets DNS hostnames

Enables debug mode

14. Which command generates a certificate signing request for VPN authentication?

Openssl req -new

Openssl cert -create

Openssl ca -sign

Openssl x509 -req

15. IPSec operates at which OSI layer?

Layer 2 (Data Link)

Layer 3 (Network)

Layer 4 (Transport)

Layer 7 (Application)

16. Which iptables rule allows VPN traffic through the firewall on port 1194?

Iptables -A INPUT -p udp --dport 1194 -j ACCEPT

Iptables -D INPUT -p udp --dport 1194

Iptables -F 1194

Iptables -L port 1194

17. What does the 'proto' parameter specify in an OpenVPN configuration file?

Protocol version number

Transport protocol (TCP or UDP)

Proxy settings

Authentication protocol

18. Which file stores the OpenVPN server configuration on Linux systems?

/etc/openvpn/client.conf

/etc/openvpn/server.conf

/var/openvpn/config.dat

/opt/openvpn/settings.conf

19. In Linux, which command enables IP forwarding required for VPN routing?

Sysctl net.ipv4.ip_forward=1

Iptables --forward

Route enable forward

Ifconfig forward on

20. What is the primary encryption cipher used in modern OpenVPN configurations?

DES

AES

RC4

MD5

Linux Network Pro Configuring a Linux Based VPN Server Quiz