UNIX Question and Answer – System Information
UNIX MCQ – Multiple Choice Questions for exam, interview, and Entrance Test
1. Which command is used to display detailed information about active TCP connections, including their state and port numbers, in UNIX?
a) netstat -at
b) lsof -i
c) ifconfig
d) ss -t
Answer: a) netstat -at
Explanation: The netstat -at command displays detailed information about active TCP connections in UNIX.
2. What does the command “hostname -i” display in UNIX?
a) System hostname
b) List of IP addresses associated with the system
c) System uptime
d) Disk usage statistics
Answer: b) List of IP addresses associated with the system
Explanation: The hostname -i command displays a list of IP addresses associated with the system in UNIX.
3. Which command is used to display information about active network connections and their corresponding processes in UNIX, including the process ID (PID)?
a) netstat -p
b) lsof -i
c) ifconfig
d) route
Answer: a) netstat -p
Explanation: The netstat -p command displays information about active network connections and their corresponding processes, including the process ID (PID), in UNIX.
4. What does the command “arp -n” display in UNIX?
a) ARP cache
b) Network interface configuration
c) Memory information
d) Disk usage statistics
Answer: a) ARP cache
Explanation: The arp -n command displays the ARP cache in UNIX.
5. Which command is used to display information about the system’s IP address and routing configuration in UNIX?
a) ifconfig
b) route
c) ip address show
d) netstat -r
Answer: c) ip address show
Explanation: The ip address show command is used to display information about the system’s IP address and routing configuration in UNIX.
6. What does the command “hostname -f” display in UNIX?
a) System hostname
b) Fully qualified domain name
c) System uptime
d) Disk usage statistics
Answer: b) Fully qualified domain name
Explanation: The hostname -f command displays the fully qualified domain name (FQDN) in UNIX.
7. Which command is used to display information about active UDP connections, including their local and remote addresses, in UNIX?
a) netstat -u
b) lsof -i
c) ifconfig
d) route
Answer: a) netstat -u
Explanation: The netstat -u command is used to display information about active UDP connections in UNIX.
8. What does the command “ifconfig eth0” display in UNIX?
a) System hostname
b) IP address and network configuration for interface eth0
c) System uptime
d) Disk usage statistics
Answer: b) IP address and network configuration for interface eth0
Explanation: The ifconfig eth0 command displays the IP address and network configuration for the interface eth0 in UNIX.
9. Which command is used to display detailed information about network interfaces, including their status and statistics, in UNIX?
a) netstat -i
b) ifconfig -a
c) ip link show
d) route -n
Answer: c) ip link show
Explanation: The ip link show command displays detailed information about network interfaces in UNIX.
10. What does the command “cat /etc/resolv.conf” display in UNIX?
a) Network interface configuration
b) DNS resolver configuration
c) System uptime
d) Disk usage statistics
Answer: b) DNS resolver configuration
Explanation: The cat /etc/resolv.conf command displays the DNS resolver configuration in UNIX.
11. Which command is used to display information about active TCP connections, including their local and remote addresses, in UNIX, with numerical addresses instead of resolving them to hostnames?
a) netstat -n
b) lsof -i
c) ifconfig
d) route
Answer: a) netstat -n
Explanation: The netstat -n command is used to display information about active TCP connections in UNIX with numerical addresses.
12. What does the command “cat /etc/hosts” display in UNIX?
a) System hostname
b) IP address and hostname mappings
c) System uptime
d) Disk usage statistics
Answer: b) IP address and hostname mappings
Explanation: The cat /etc/hosts command displays IP address and hostname mappings in UNIX.
13. Which command is used to display detailed information about active and passive network sockets in UNIX?
a) ss -l
b) netstat -p
c) lsof -i
d) arp -a
Answer: c) lsof -i
Explanation: The lsof -i command is used to display detailed information about active and passive network sockets in UNIX.
14. What does the command “cat /etc/network/interfaces” display in UNIX?
a) Network interface configuration
b) IP address and hostname mappings
c) System uptime
d) Disk usage statistics
Answer: a) Network interface configuration
Explanation: The cat /etc/network/interfaces command displays network interface configuration in UNIX.
15. Which command is used to display information about the system’s IP routing table in UNIX, with numerical addresses instead of resolving them to hostnames?
a) route -n
b) netstat -r
c) ip route show
d) arp -a
Answer: a) route -n
Explanation: The route -n command is used to display information about the system’s IP routing table in UNIX with numerical addresses.
16. What does the command “cat /etc/nsswitch.conf” display in UNIX?
a) Network interface configuration
b) System hostname
c) Name Service Switch configuration
d) Disk usage statistics
Answer: c) Name Service Switch configuration
Explanation: The cat /etc/nsswitch.conf command displays the Name Service Switch configuration in UNIX.
17. Which command is used to display information about active and passive network sockets, including their state and process IDs, in UNIX?
a) ss -tuln
b) netstat -p
c) lsof -i
d) arp -a
Answer: c) lsof -i
Explanation: The lsof -i command is used to display information about active and passive network sockets, including their state and process IDs, in UNIX.
18. What does the command “cat /etc/resolv.conf” display in UNIX?
a) DNS resolver configuration
b) Network interface configuration
c) System uptime
d) Disk usage statistics
Answer: a) DNS resolver configuration
Explanation: The cat /etc/resolv.conf command displays the DNS resolver configuration in UNIX.
19. Which command is used to display information about the system’s IP address and hostname mappings in UNIX?
a) hostname -i
b) cat /etc/hosts
c) ifconfig
d) netstat -r
Answer: b) cat /etc/hosts
Explanation: The cat /etc/hosts command is used to display information about the system’s IP address and hostname mappings in UNIX.
20. What does the command “cat /proc/net/dev” display in UNIX?
a) Network interface configuration
b) System uptime and load average
c) Memory information
d) Disk usage statistics
Answer: a) Network interface configuration
Explanation: The cat /proc/net/dev command displays network interface configuration in UNIX.
21. Which command is used to display information about active TCP connections, including their local and remote addresses, in UNIX, sorted by state?
a) netstat -atn
b) lsof -i
c) ifconfig
d) ss -t
Answer: a) netstat -atn
Explanation: The netstat -atn command is used to display information about active TCP connections in UNIX, sorted by state.
22. What does the command “cat /etc/hostname” display in UNIX?
a) System hostname
b) IP address and hostname mappings
c) DNS resolver configuration
d) Disk usage statistics
Answer: a) System hostname
Explanation: The cat /etc/hostname command displays the system hostname in UNIX.
23. Which command is used to display detailed information about network interfaces, including their status and statistics, in UNIX, with numerical addresses instead of resolving them to hostnames?
a) netstat -i
b) ifconfig -a
c) ip link show
d) route -n
Answer: c) ip link show
Explanation: The ip link show command is used to display detailed information about network interfaces in UNIX with numerical addresses.
24. What does the command “cat /etc/network/interfaces” display in UNIX?
a) Network interface configuration
b) IP address and hostname mappings
c) DNS resolver configuration
d) Disk usage statistics
Answer: a) Network interface configuration
Explanation: The cat /etc/network/interfaces command displays network interface configuration in UNIX.
25. Which command is used to display information about active and listening sockets, including their state and process IDs, in UNIX?
a) ss -tuln
b) netstat -p
c) lsof -i
d) arp -a
Answer: c) lsof -i
Explanation: The lsof -i command is used to display information about active and listening sockets, including their state and process IDs, in UNIX.
26. Which command is used to display the status of network interfaces, including their IP addresses and MAC addresses, in UNIX?
a) ifconfig
b) ip addr show
c) netstat -i
d) arp -a
Answer: b) ip addr show
Explanation: The ip addr show command displays the status of network interfaces, including their IP addresses and MAC addresses, in UNIX.
27. What does the command “cat /etc/services” display in UNIX?
a) System hostname
b) IP address and port number mappings
c) DNS resolver configuration
d) Disk usage statistics
Answer: b) IP address and port number mappings
Explanation: The cat /etc/services command displays IP address and port number mappings in UNIX.
28. Which command is used to display detailed information about active TCP connections, including their state and process IDs, in UNIX?
a) netstat -tp
b) lsof -i
c) ifconfig
d) ss -t
Answer: a) netstat -tp
Explanation: The netstat -tp command is used to display detailed information about active TCP connections, including their state and process IDs, in UNIX.
29. What does the command “cat /proc/net/tcp” display in UNIX?
a) Detailed TCP/IP stack configuration
b) Network interface configuration
c) Memory information
d) Disk usage statistics
Answer: a) Detailed TCP/IP stack configuration
Explanation: The cat /proc/net/tcp command displays detailed TCP/IP stack configuration in UNIX.
30. Which command is used to display information about active UDP connections, including their local and remote addresses, in UNIX, sorted by state?
a) netstat -un
b) lsof -i
c) ifconfig
d) ss -u
Answer: a) netstat -un
Explanation: The netstat -un command is used to display information about active UDP connections in UNIX, sorted by state.
31. What does the command “cat /etc/hostname” display in UNIX?
a) System hostname
b) Fully qualified domain name
c) DNS resolver configuration
d) Disk usage statistics
Answer: a) System hostname
Explanation: The cat /etc/hostname command displays the system hostname in UNIX.
32. Which command is used to display information about active and listening sockets, including their state and process IDs, in UNIX, sorted by process ID?
a) ss -tp
b) netstat -lp
c) lsof -i
d) arp -a
Answer: c) lsof -i
Explanation: The lsof -i command is used to display information about active and listening sockets, including their state and process IDs, in UNIX, sorted by process ID.
33. What does the command “cat /proc/net/dev” display in UNIX?
a) Network interface configuration
b) System uptime and load average
c) Memory information
d) Disk usage statistics
Answer: a) Network interface configuration
Explanation: The cat /proc/net/dev command displays network interface configuration in UNIX.
34. Which command is used to display information about active TCP connections, including their local and remote addresses, in UNIX, with extended details?
a) netstat -atv
b) lsof -i
c) ifconfig
d) ss -t
Answer: a) netstat -atv
Explanation: The netstat -atv command is used to display information about active TCP connections in UNIX with extended details.
35. What does the command “cat /proc/net/arp” display in UNIX?
a) ARP cache
b) Network interface configuration
c) Memory information
d) Disk usage statistics
Answer: a) ARP cache
Explanation: The cat /proc/net/arp command displays the ARP cache in UNIX.
36. Which command is used to display detailed information about network interfaces, including their status, statistics, and hardware addresses, in UNIX?
a) ifconfig -a
b) ip addr show
c) netstat -i
d) route -n
Answer: b) ip addr show
Explanation: The ip addr show command is used to display detailed information about network interfaces, including their status, statistics, and hardware addresses, in UNIX.
37. What does the command “cat /etc/resolv.conf” display in UNIX?
a) DNS resolver configuration
b) Network interface configuration
c) System uptime
d) Disk usage statistics
Answer: a) DNS resolver configuration
Explanation: The cat /etc/resolv.conf command displays the DNS resolver configuration in UNIX.
38. Which command is used to display information about the system’s IP address and hostname mappings in UNIX, sorted by IP address?
a) hostname -i
b) cat /etc/hosts
c) ifconfig
d) netstat -r
Answer: b) cat /etc/hosts
Explanation: The cat /etc/hosts command is used to display information about the system’s IP address and hostname mappings in UNIX, sorted by IP address.
39. What does the command “cat /proc/sys/net/ipv4/tcp_keepalive_time” display in UNIX?
a) System uptime and load average
b) CPU information
c) TCP keepalive time interval
d) Disk usage statistics
Answer: c) TCP keepalive time interval
Explanation: The cat /proc/sys/net/ipv4/tcp_keepalive_time command displays the TCP keepalive time interval in UNIX.
40. Which command is used to display information about active and listening sockets, including their state and process IDs, in UNIX, with numeric user and group IDs?
a) ss -tp
b) netstat -lp
c) lsof -ni
d) arp -a
Answer: c) lsof -ni
Explanation: The lsof -ni command is used to display information about active and listening sockets, including their state and process IDs, in UNIX, with numeric user and group IDs.
41. What does the command “cat /proc/net/tcp” display in UNIX?
a) Detailed TCP/IP stack configuration
b) Network interface configuration
c) Memory information
d) Disk usage statistics
Answer: a) Detailed TCP/IP stack configuration
Explanation: The cat /proc/net/tcp command displays detailed TCP/IP stack configuration in UNIX.
42. Which command is used to display information about active UDP connections, including their local and remote addresses, in UNIX, with extended details?
a) netstat -unv
b) lsof -i
c) ifconfig
d) ss -u
Answer: a) netstat -unv
Explanation: The netstat -unv command is used to display information about active UDP connections in UNIX, with extended details.
43. What does the command “cat /etc/network/interfaces” display in UNIX?
a) Network interface configuration
b) IP address and hostname mappings
c) DNS resolver configuration
d) Disk usage statistics
Answer: a) Network interface configuration
Explanation: The cat /etc/network/interfaces command displays network interface configuration in UNIX.
44. Which command is used to display information about active TCP connections, including their local and remote addresses, in UNIX, with human-readable output?
a) netstat -ath
b) lsof -i
c) ifconfig
d) ss -t
Answer: a) netstat -ath
Explanation: The netstat -ath command is used to display information about active TCP connections in UNIX with human-readable output.
45. What does the command “cat /proc/sys/net/ipv4/tcp_syn_retries” display in UNIX?
a) System uptime and load average
b) CPU information
c) Number of TCP SYN retries
d) Disk usage statistics
Answer: c) Number of TCP SYN retries
Explanation: The cat /proc/sys/net/ipv4/tcp_syn_retries command displays the number of TCP SYN retries in UNIX.
46. Which command is used to display information about active and passive network sockets, including their state and process IDs, in UNIX, with numeric user and group IDs?
a) ss -tuln
b) netstat -lp
c) lsof -ni
d) arp -a
Answer: c) lsof -ni
Explanation: The lsof -ni command is used to display information about active and passive network sockets, including their state and process IDs, in UNIX, with numeric user and group IDs.
47. What does the command “cat /proc/net/dev” display in UNIX?
a) Network interface configuration
b) System uptime and load average
c) Memory information
d) Disk usage statistics
Answer: a) Network interface configuration
Explanation: The cat /proc/net/dev command displays network interface configuration in UNIX.
48. Which command is used to display information about active TCP connections, including their local and remote addresses, in UNIX, with extended details?
a) netstat -atv
b) lsof -i
c) ifconfig
d) ss -t
Answer: a) netstat -atv
Explanation: The netstat -atv command is used to display information about active TCP connections in UNIX with extended details.
49. What does the command “cat /proc/net/arp” display in UNIX?
a) ARP cache
b) Network interface configuration
c) Memory information
d) Disk usage statistics
Answer: a) ARP cache
Explanation: The cat /proc/net/arp command displays the ARP cache in UNIX.
50. Which command is used to display detailed information about network interfaces, including their status, statistics, and hardware addresses, in UNIX, with extended details?
a) ifconfig -a
b) ip addr show
c) netstat -i
d) route -n
Answer: b) ip addr show
Explanation: The ip addr show command is used to display detailed information about network interfaces, including their status, statistics, and hardware addresses, in UNIX, with extended details.
