Amer Networks SS2R48G4i V2 - Manual (Page 160)

SS2R24G4i/SS2R48G4i
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Chapter 17 Port Channel Configuration
17.1 Introduction to Port Channel
To understand Port Channel, Port Group should be introduced first. Port Group is a group of
physical ports in the configuration level; only physical ports in the Port Group can take part in link
aggregation and become a member port of a Port Channel. Logically, Port Group is not a port but a port
sequence. Under certain conditions, physical ports in a Port Group perform port aggregation to form a
Port Channel that has all the properties of a logical port, therefore it becomes an independent logical
port. Port aggregation is a process of logical abstraction to abstract a set of ports (port sequence) with
the same properties to a logical port. Port Channel is a collection of physical ports and used logically as
one physical port. Port Channel can be used as a normal port by the user, and can not only add
network’s bandwidth, but also provide link backup. Port aggregation is usually used when the switch is
connected to routers, PCs or other switches.
Fig 17-1 Port aggregation
As shown in the above figure, Switch1 is aggregated to a Port Channel, the bandwidth of this Port
Channel is the total of all the four ports. If traffic from SwitchA needs to be transferred to SwitchB
through the Port Channel, traffic allocation calculation will be performed based on the source MAC
address and the lowest bit of target MAC address. The calculation result will decide which port to
convey the traffic. If a port in Port Channel fails, the other ports will undertake traffic of that port through
a traffic allocation algorithm. This algorithm is carried out by the hardware.
SS2R24/48G4i switch switch offers 2 methods for configuring port aggregation manual Port
Channel creation and LACP (Link Aggregation Control Protocol) dynamic Port Channel creation. Port
aggregation can only be performed on ports in full-duplex mode.
For Port Chansnel to work properly, member ports of the Port Channel must have the same properties
as follows
z All ports are in full-duplex mode.
z All Ports are of the same speed.