Fluke Computer Accessories IP Application Names, DiffServ Names, Hostname Resolution Settings

User’s Guide – version 3.5 NetFlow Tracker

IP Application Names

NetFlow Tracker receives application information in the form of a protocol number and port number. These correspond directly to specific network applications. Many are predefined (well-known ports) while others (registered ports) are defined by the software manufacturer. NetFlow Tracker comes configured with the well-known ports as well as many others. You can edit this list yourself with this page. By default, ports below 1024 are not shown on this page as they normally don’t need to be changed but, if required, these can be shown by clicking (more…) in the title of the Port column. A comprehensive list of all the well-known and registered ports is available at http://www.iana.org/assignments/port-numbers.

Often, a single application port is not enough to correctly identify an application. NetFlow Tracker also allows you to create multiple grouped applications, with each grouped application containing multiple rules. A rule consists of at least one of a range of IP addresses, a range of port numbers for a given protocol, a traffic class or an identified application. Traffic with the source or destination address and port passing at least one rule is considered to be part of that application. If there is any uncertainty, for example if two or more applications match a given piece of traffic, the highest- precedence application is chosen. Every grouped application has a configurable precedence, and every grouped application is of a higher precedence than every simple, single-port application.

To define a grouped application you must first give it a unique identifier and a name; you can then add rules to it. The application identifier is used in long-term data to identify the application so it is not possible to change the identifier of an existing grouped application; for the same reason please be careful about deleting grouped applications.

DiffServ Names

NetFlow Tracker can filter and report by differentiated service code point; you can assign names to each of the 64 code points here. The standard code point names are already configured.

Hostname Resolution Settings

This page lets you configure aspects of the resolution of hostnames for addresses encountered on reports. These are cached to increase reporting speed and reduce the amount of network traffic generated by the NetFlow Tracker when generating a report. You can change how long a resolved hostname is cached for, the default being 30 minutes, and how long a failure to resolve a hostname for a given address is remembered, the default being 10 seconds. You can also control the size of the cache and the number of threads used to resolve hostnames. If you find that hostname resolution is not working, click “Defaults” to put the settings back to useful default values. Click “Ok” to accept your changes or “Cancel” to abort.

Should you wish to clear the cache of resolved hostnames, disable resolution by clearing “Enable hostname resolution” and clicking “Ok”, then go back into the configuration page and enable resolution again by checking “Enable hostname resolution” and clicking “Ok”.

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