Questão de Linux Administration #019e3987

Summary

This question tests your understanding of network diagnostic tools. The goal is to identify a broken router (a network device that forwards packets) between your local machine and a remote machine. traceroute is the correct tool because it traces the path packets take and can show where they stop or are lost.

How it Works

traceroute works by sending packets with increasing Time-To-Live (TTL) values. Each router along the path decrements the TTL; when TTL reaches zero, the router sends an ICMP Time Exceeded message back to the sender. By recording the source IP of these messages, traceroute maps the route. If a router is broken, packets may not reach the next hop, causing timeouts or incomplete paths.

Why the correct answer is right

E. traceroute – It explicitly shows each hop (router) between source and destination. If a router is broken, you'll see either no response (timeouts) or the path stops at that router. This directly identifies the problematic router.

Why incorrect options are wrong

• A. ps – Lists running processes on the local machine; has nothing to do with network routing.
• B. netstat – Displays network connections, routing tables, and interface statistics. While it can show the local routing table, it cannot trace the path to a remote host or identify a broken router along the way.
• C. nslookup – Queries DNS to resolve hostnames to IP addresses. It does not test network connectivity or routing.
• D. ifconfig – Configures and displays network interface parameters (IP, netmask, etc.) on the local machine. It does not perform path discovery.