33. A person is troubleshooting a network issue and needs to see a list of all active TCP network connections on this computer. Which Linux command should be used?
Answer: A
netstat is the appropriate command to list all active TCP network connections on a Linux computer.
The command 'netstat' provides a detailed view of network connections, including active TCP connections, making it the best choice for this task.
A) netstat
This option is correct because the 'netstat' command is specifically designed to display active connections and listening ports for TCP and UDP on a Linux system. It provides comprehensive information about the network status, which is essential for troubleshooting network issues.
B) dig
The 'dig' command is incorrect in this context as it is primarily used for querying DNS name servers to retrieve information about domain names. It does not provide information on active network connections.
C) ifconfig
While 'ifconfig' is used to configure and display network interfaces on a Linux system, it does not list active TCP connections. Therefore, it is not suitable for troubleshooting network connections.
D) nslookup
The 'nslookup' command is also incorrect for this purpose, as it is used to query DNS records and resolve domain names to IP addresses. It does not provide any detail on the active TCP connections on a system.
Conclusion
In summary, 'netstat' is the only command provided that effectively lists all active TCP connections, making it the definitive correct choice. The other options, while useful for different networking tasks, do not fulfill the requirement of displaying network connections and thus are not suitable for this troubleshooting scenario.