Avaya Cajun P882 User Manual page 161

50 Series
Forwarding
Engines and
Fabric Ports
Load Share
Function
Hunt Group
Example
Avaya P550R, P580, P880, and P882 Multiservice Switch User Guide, Version 5.3.1
Using VLANs, Spanning Tree, Hunt Groups, and VTP Snooping
each have a Forwarding Engine and use the second fabric port. The
Forwarding Engines are distributed on a one to one basis for the 80
series Gigabit media modules. For example the 8 port 1000 TX, the
first four ports have four Forwarding Engines, one for each Gigabit
port (1-4), and uses one fabric port, the other four ports (5-8) also
have four Forwarding Engines, which use the second fabric port.
On a 50 series layer 3 module, each fabric port has two Forwarding
Engines, one for layer 3 traffic, and one for layer 2 traffic. All layer 3
traffic will be associated with one Forwarding Engine and all the
layer 2 traffic will be associated with the other Forwarding Engine.
Example, the twelve-port 10/100 layer 3 50 series media module,
layer 3 traffic is coming in the first port and the last port, (ports
1,12). Using the 80 series even distribution, the first six ports are
associated with one FE and the second six ports with the second FE,
and distributed across both fabric ports.
This is different for the 50 series modules. The twelve port layer 3 50
series media module, all twelve ports are associated with one
Forwarding Engine for layer 3 traffic and one Forwarding Engine for
layer 2 traffic. In addition only one fabric port is used for all twelve
ports.
Hunt Groups load share by directing different traffic to different
ports in the hunt group, when sending traffic to a particular user.
Load sharing is done in a round-robin fashion across the ports in a
hunt group. This is based upon BOTH the Destination MAC
Address and the Source Forwarding Engine. The Hunt Group
ports on which unicast packets traverse to reach the destination
depends upon the source user's associated Forwarding Engine.
Refer to Figure 4-16. One port in the Hunt Group will be designated
as the "Base"/"Flood Port". All flood traffic for all VLANs is sent
through this port only. All ports are members of all VLANs
associated with the Hunt Group Base port. There are 8 non-member
Forwarding Engines. Load sharing is accomplished by using the
combination of the Source Forwarding engine and the Destination
MAC Address to assign a hunt group port. Users A and B are
associated with FE#9 and therefore the first port in the Hunt group
will be used for unicast packets from A to Destination E and from B
to E. Users C and D are associated with FE#10 and therefore the
second port in the Hunt Group will be used for unicast packets from
C to E and D to E.
When MAC Address E is learned, it is assigned to the first hunt
group port for FE#1, the second hunt group port for FE#2, the first
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