Default Parameters for TopSitesTest

For each web site that is configured for monitoring, this test reports the amount of data transmitted and received and the bandwidth utilized by that site. Web sites that consistently invite heavy traffic and consume excessive bandwidth can be identified in the process. If such sites are mission-critical business sites/applications, then this information will help you to determine the bandwidth required to ensure the peak performance of the sites and thus enable you to right-size your network. If such sites are inconsequential to your business, then this information will point you to where bandwidth is spent unnecessarily; this in turn will prompt you to initiate measures to control/regulate accesses to such sites.

This page depicts the default parameters that need to be configured for the TopSitesTest test.

• The TEST PERIOD list box helps the user to decide how often this test needs to be executed.

• Network latencies and processing bottlenecks can sometimes cause netflow records to be transmitted slowly to the NetFlow collector. In such a situation, you can instruct the collector to either process or ignore the delayed NetFlow records. If you want the metrics reported to pertain to current NetFlow records only, then you may choose to ignore the delayed records. In this case, set the PROCESS TAINTED PACKETS flag to No. If you want old NetFlow records to also be considered when identifying top sources and reporting their traffic statistics, then set this flag to Yes. Typically, any NetFlow record that takes 10 minutes or over to reach the NetFlow collector is deemed a tainted/delayed record.

• By default, NetFlow is designed to process all IP packets on an interface. This is why, the SAMPLING flag is set to No by default. In some environments however, e.g. on Internet backbones, processing all IP packets can be too costly, due to the extra processing required for each packet and large number of simultaneous flows. This is where sampling is useful. In such environments, set the SAMPLING flag to Yes.

  Once this is done, then each interface will process only 1 packet out of a configured number of packets. Specify the number of packets from which this 1 packet should be picked in the SAMPLING RATE text box. For instance, to pick 1 out of 1000 packets for sampling, set the Sampling Rate to 1000. Where Sampling is enabled, all NetFlow metrics - particularly, metrics on traffic volume - will be adjusted based on the SAMPLING RATE you specify.

• The DD FREQUENCY refers to the frequency with which detailed diagnosis measures are to be generated for this test. The default is 1:1. This indicates that, by default, detailed measures will be generated every time this test runs, and also every time the test detects a problem. You can modify this frequency, if you so desire. Also, if you intend to disable the detailed diagnosis capability for this test, you can do so by specifying none against DD FREQUENCY.

• Once the above values are provided, click on the UPDATE button to register the changes made.

When changing default configurations of tests, the values with “$” indicate variables that will be replaced by the eG system according to the specific server being managed - for instance, $hostName is the host/nickname of the target host, $port is the port number of the server being monitored. E.g., for a server xyz:80, $hostName will be changed automatically by the eG manager to “xyz*” and $port will be changed to “80” when configuring a test.