Test your skills on Network Monitoring Techniques
1. Users on a network are complaining that they are unable to access FTP service on the server. Which tool and methodology can the admin use to check if the port for FTP is open from his system.
2. Which command on a Windows system can be used to find the list of open TCP connections.
3. Explain a methodology by which traffic to an internet router can be captured and used for later analysis.
4. Users are complaining they are unable to ping a particular system on the network. How can the admin monitor the issue.
5. Name one tool which can be used for monitoring the bytes sent and received on the network card of a server.
6. Explain two techniques which you would use to monitor and analyze slow applications.
7. Explain two techniques which you would use to monitor and analyze slow networks.
1. NMAP, which is a port scanning tool can be used to scan the server and check if FTP port 21 is open. TCP port scanning can be used for the purpose.
2. netstat command can be used to find connections open on the system.
3. Using a combination of port mirroring and protocol analyzer tool like wireshark, packets to the internet router can be captured and used for later analysis.
4. The admin can use wireshark and check if ARP requests and appropriate responses are being received. Also presence of firewall on the system can be checked.
5. netstat can be used for checking sent and received bytes on the server.
6. Monitor the number of connections to the specific port on the system using netstat. This would help to monitor if the connection threshold limit for the application has been reached. Using wireshark , the number of TCP reset connections from the application port can be analyzed. A large number of TCP reset connections is a cause for slow application.
7. Using wireshark, broadcast packets can be analyzed on the network, which is a major cause for slow networks. 100 ping packets can be sent to a system on the network, and the number of packets dropped which would indicate a slow network.
Network Monitoring – Tools & Techniques