Net Optics Director Switch User Manual


  Open as PDF
of 59
 
Director
49
Filter parameters
Switches and lters are dened using the lteraddandlterinscommands. The lteradd command syntax is:
lter ipv6=y add in_ports=<portlist> <lter_parameter_list> action=<redir|drop> redir_ports=<portlist>
The <lter_parameter_list> is a sequence of zero or more of the lter qualiers as listed in the following table.
If the <lter_parameter_list> is empty, the lteradd command species an aggregation of the trafc received on all of
the in_ports. If the action=redir, the aggregated trafc stream is regenerated to all of the redir_ports.
If the <lter_parameter_list> contains lters, aggregation and regeneration take place as described in the previous
paragraph. However, the lters are applied to the aggregated trafc stream before it is copied to the monitor ports. If
multiple lter qualiers are specied, a packet must satisfy all of the lter qualiers in order to be copied to the monitor
ports. In other words, the lter qualiers are combined with a logical AND condition. A logical OR condition can be
created by using multiple lteraddcommands with identical port lists.
The lteraddandlterinscommands dene lters but do not activate them. A subsequent ltercommit or commit
command must be executed to activate the lters. This mechanism enables an interrelated group of lters to be activated
simultaneously. It also allows you to double-check your lter denitions before you activate them. The commit command
also rewrites the default Director conguration (the defaultcfg le), while lter commit does not.
Note that IPv6 and IPv4 lters are maintained separately. It is important to include the "ipv6=y" argument when dealing
with IPv6 lters, and omit it when dealing with IPv4 lters.
It is also important to note that packets are ltered using a Content Addressable Memory or CAM. Each lter is a CAM
entry, and the CAM is lled in the order that the lteraddcommands are entered. Filter ins commands create lters
in specic locations in the CAM. When a packet is processed, the rst lter in the CAM that matches the packet is the
only lter that is activated. Each packet can activate exactly zero or one lters. See Understandlterinteractions
near the end of Chapter 3 for examples.
All supported lter qualiers are shown in the table on the following page.
 previous next