System information

Switch Setup Dashboard 219
Switch Setup Dashboard
see “Main Switch Dashboard – Switch Setup Tab” on page 309.
Select Address Table for Local Observer
see “Multiple Address Tables” on page 204.
Filter Setup for Selected Probe
Lets you filter which packets to capture by applying various criteria.
Menu Path
Tools->Filter Setup for Selected Probe
Purpose
Packet filtering lets you configure Observer to discard the packets you are not interested in
so that you can focus on the traffic you are interested in. Without filtering, it can be much
more difficult to find the packets that will help you solve a problem or focus on
problematic network stations and devices.
Filters consist of rules that cause a packet to be included or excluded during packet
captures and certain statistical modes. Each rule is a condition test applied to each packet
sensed. Depending on the type of network you are analyzing, you can test for over a dozen
types of conditions, including:
• sending and receiving addresses (MAC, IP, DLCI)
• which protocol packets are part of
• whether packets include a particular ASCII, hex, or bit string starting from a specified
offset
• whether packets include a particular numeric value at a specified offset
You can either include or exclude packets based on the results returned for each packet by
each rule in the filter.
Types of Filter Rules
As noted, there are a number of different rule types. Note that not all rule types (WAN and
Wireless) apply to all network types, and others only apply to post-capture filtering (for
example, rules that filter for packets that have been annotated with Observer or Expert
packets generated by Observer).
If you apply a rule that is not relevant to the current capture or post capture filter scenario,
that rule is ignored.