Troubleshooting with APS

The APS can be used to troubleshoot complex IT problems that depend on multiple variables. Variables such as Connection Time (CT), Server Response Time (SRT), Client Response Time (CRT), Round Trip Time (RTTin + RTTout), Retransmission Delay (RD) and Retransmission Rate (RR). By having the value of these variables at a glance, an experienced network administrator can immediately identify and resolve the root cause of a problem.

For example, if an end user is complaining about having to wait a long time to connect to the network, the APS will allow a network administrator to immediately localize and troubleshoot the problem. If the APS shows that there is a high CRT, this indicates that the problem exists on the clients laptop. If the APS shows there is a very high SRT, this indicates that the problem exists on the server and can be due to a bad TCP/IP stack or the need to implement load balancing. If there is a high RR, this would indicate the need to increase bandwidth capacity over the link between the client laptop and the server hosing the application.

Additionally, the APS captures and displays DNS messages. These messages indicate which client has done a request, to which server the request was made and what was the request. The APS also shows the error codes returned from the DNS server. These error codes can be used to troubleshoot problems that may exist on the DNS server as well as problems that may exist on the clients. For example, if a DNS server returns an error code of 3, it means that the requested domain is non-existant. Therefore, the DNS server administrator needs to add the requested domain to the DNS servers record list.

APS also captures and displays ICMP error messages. If the ICMP error message is Port Unreachable, it means that a client tried to connect to a server using a UDP port that is not available. Therefore, the server administrator needs to connect to the server and start the service in question. Another example, if the ICMP error message is Host Unreachable, it means that a client tried to reach a server in another network and the server was not available. Therefore, the client administrator may need to reconfirgure the client with the correct server address.