Foundry Networks Switch and Router Installation And Configuration Manual page 301

Trunk Group Rules
• You can configure up to 64 trunk groups on a Chassis device, and up to four trunk groups on all Stackable
devices except the TurboIron/4. The TurboIron/4 allows up to three trunk groups.
• Each trunk group must start with a primary port. The primary port is always the lowest number in the
following port ranges:
• Chassis devices: 1 – 4, 5 – 8, 9 – 12, 13 – 16 and 17 – 18 and 21 –24
NOTE: You can configure up to 12 trunk groups on a chassis 24-port 10/100 module. The 24-port 10/100
modules have the following primary ports: 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, and 23. See Figure 10.6.
• TurboIron/4: 1 – 2, 3 – 4 and 5 – 6
• TurboIron/8: 1 – 4 and 5 – 8 or 1 – 2, 3 – 4, 5 – 6, 7 – 8
• Other Stackable devices: 1 – 2, 3 – 4, 5 – 6, 7 – 8, 9 – 10, 11 – 12, 13 – 14, 15 – 16, 17 – 18, 19 – 20, 21
– 22, 23 – 24, and 25 – 26
NOTE: You still can configure 4-port trunk groups on a Stackable device, but you must begin a 4-port trunk
group on one of the following primary ports: 1, 5, 9, 13, 17, or 21.
• Port assignment must be contiguous. The port range cannot contain gaps. For example, you can configure
ports 1, 2, 3, and 4 together as a trunk group but not ports 1, 3, and 4 (excluding 2).
• Port assignment cannot be across multiple trunk group boundaries. For example, on a Stackable device,
ports 4 and 5 cannot be in the same trunk group.
• All the ports must be connected to the same device at the other end.
• All trunk group member properties must match the lead port of the trunk group with respect to the following
parameters:
• Port tag type (untagged or tagged port)
• Port speed and duplex
• QoS priority
To change port parameters, you must change them on the primary port. The software automatically applies
the changes to the other ports in the trunk group.
December 2000
Configuring Basic Features
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