3Com CoreBuilder 3500, Implementation Manual, Page: 70 / 592

70 C
HAPTER
4: P
HYSICAL
P
ORT
N
UMBERING
Trunk Changes
■
If you remove a module of a specific type that has trunks and replace
it with a module of another type, the new ports do not become part
of the trunk. When you define a trunk, the trunk is associated with a
specific media type (100 Mb, Gigabit, or FDDI).
Example
If you replace a 10/100 Ethernet module in slot 1 (that has a trunk on
ports 5 and 6) with an FDDI module, the new FDDI ports 5 and 6 do
not become part of the trunk. In this case, removing the 10/100
Ethernet module causes the 100 Mb trunk to lose all of its ports,
although the trunk itself remains configured on the system.
Special Case: If you have four trunks and you replace a module of a given
type with a Gigabit Ethernet module, the system cannot recognize the
new Gigabit Ethernet module, because this module type uses a trunk
resource. In this case, you must remove one of your trunks before you
add the Gigabit Ethernet module (for example, a trunk associated with
the removed module).
■
If you replace a module that has a trunk spanning another module,
after the change, the trunk is missing the ports associated with the
removed module.
Example
If a trunk spans two 10/100 Ethernet modules (ports 5-8) in slots 1
and 2, and the module in slot 1 is replaced by an FDDI module, after
the change, the trunk display shows ports 5 and 6 as
Missing
, but the
trunk still has the ports from the other Ethernet module (ports 7
and 8).
For more information on trunking, see Chapter 8. For information on
VLANs, see Chapter 9.