Exam N10-008 topic 1 question 750 discussion

With netstat he can check if port 80 and 443 are running

The administrator should run the netstat command first. This will help check if the web server is listening on the correct port (usually port 80 for HTTP or port 443 for HTTPS) and if there are any established connections or issues with network sockets.

When users can ping the server IP but cannot access the web server via a browser, it indicates that basic network connectivity is present, but there may be issues with the specific service (HTTP/HTTPS) or the traffic reaching the server. Using tcpdump allows the systems administrator to capture and analyze network packets on the server. By running tcpdump, the administrator can check if requests to the web server (typically on ports 80 for HTTP or 443 for HTTPS) are reaching the server. This is crucial for diagnosing whether the web server is receiving traffic from clients.

B. netstat The command netstat -tulpn | grep 80 -t: Shows TCP connections. -u: Shows UDP connections. -l: Shows only listening sockets. -p: Shows the process ID and name of the process using the socket. -n: Shows numerical addresses instead of resolving hostnames. grep 80 filters the output to show only lines containing port 80 and which process is associated with it.

C. tcpdump When investigating why users cannot reach a Linux web server with a browser but can ping the server IP, the administrator should run the tcpdump command on the server first. Tcpdump is a packet analyzer that allows the administrator to capture and analyze network traffic in real-time. By running tcpdump, the administrator can inspect the packets arriving at the server, which can provide insights into whether the server is receiving HTTP traffic and whether there are any issues with the communication. Options A (traceroute), B (netstat), and D (arp) are useful for different purposes but may not directly help diagnose the issue at hand. Traceroute shows the path taken by packets, netstat displays network statistics and connections, and arp resolves IP addresses to MAC addresses. Tcpdump is better suited for capturing and analyzing the actual traffic arriving at the server, helping identify potential issues with web traffic.

C tcpdump tcpdump is a packet analyzer tool used to capture and display TCP/IP and other packets being transmitted or received over a network. By running tcpdump on the Linux web server, the administrator can examine the incoming network traffic and check if requests to the web server are reaching the server and if the server is responding to those requests. This can help identify any potential issues with the network traffic flow or the web server configuration.