Allied Telesis AT-S62 - Manual (Page 123)

AT-S62 User’s Guide
Section I: Basic Operations 123
❑ When cabling a trunk, the order of the connections should be
maintained on both nodes. The lowest numbered port in a trunk
on the switch should be connected to the lowest numbered port
of the trunk on the other device, the next lowest numbered port
on the switch should be connected to the next lowest numbered
port on the other device, and so on.
For example, assume that you are connecting a trunk between
two AT-8524M switches. On the first AT-8524M switch you had
chosen ports 12, 13, 14, 15 for the trunk. On the second AT-8524M
switch you had chosen ports 21, 22, 23, and 24. To maintain the
order of the port connections, you would connect port 12 on the
first AT-8524M switch to port 21 on the second AT-8524M switch,
port 13 to port 22, and so on.
❑ You can create a port trunk of the ports in two expansion modules
in an AT-8524M switch, providing that the ports are of the same
medium type and have the same operating specifications.
Port Operating
Specifications
The speed, duplex mode, flow control, and back pressure settings must
be the same for all the ports of a port trunk. When you create a port
trunk, the management software copies the current settings of the
lowest numbered port in the trunk to the other ports. For example, if you
create a port trunk consisting of ports 5 to 8, the parameter settings for
port 5 are copied to ports 6, 7, and 8 so that all the ports of the trunk
have the same settings. For this reason it is recommended that before
creating a port trunk you first examine the settings of the lowest number
port that will be in the trunk and verify that it has the correct settings.
Once you have created a port trunk, do not change the speed, duplex
mode, flow control or back pressure of any port in the trunk without
making the same change to the other ports.
Load
Distribution
Methods
There are two steps for creating a port trunk. The first is to identify the
ports on the switch that are to function as the port trunk. The second is
to select a load distribution method. This second step is important
because unless you select the correct distribution method for your
configuration, the switch might not evenly distribute the load across all
the links of a trunk. Naturally, this could greatly diminish the value of the
port trunk.
The AT-S62 management software offers six load distribution methods.
They are:
❑ Source MAC Address (Layer 2)
❑ Destination MAC Address (Layer 2)
❑ Source MAC Address / Destination MAC Address (Layer 2)