3Com 4007, Implementation Manual, Page: 142 / 684

142 C
HAPTER
7: P
HYSICAL
P
ORT
N
UMBERING
Using Table 34: Examples
Suppose you installed a 24-port Switch Fabric Module. Next, you installed
a 36-port Fast Ethernet Layer 2 Switching Module in slot 4. After both
module’s boot sequences were finished, you should see LED #7 and #8 on
the switch fabric module to be lighted green. This indicates that the
switching module recognizes that there is a module in slot 4. However,
from Table 34, notice that the corresponding switch fabric port numbers
are 13 and 14, respectively. Also notice that port numbers 15 and 16 on
the switch fabric module (and LEDs 19 and 20) will not be used.
Next, in that same chassis, suppose you installed a 4-port Gigabit
Ethernet Multilayer Switching Module in slot 5. After it completed its
boot sequence, you would look for LED# 9, 10, 21, and 22 to become
lighted on the switch fabric module. However, from Table 34, notice that
the corresponding switch fabric port numbers are 17, 18, 19, and 20,
respectively.
Key Guidelines for
Implementation
To ensure that you understand the port numbering that the system
reports for certain aspects of your configuration (bridging information,
trunks, and virtual LANs), observe these guidelines when you configure
your system:
■
Before you attempt to configure any bridging parameters, determine
your physical port configuration.
■
If you use trunking to group ports, configure your trunks before you
attempt to configure any Virtual LANs (VLANs). Be sure that you
understand how trunking associates a group of ports with a trunk.
(See Chapter 12.) These associations affect the following situations:
■
When you perform an operation for which you must specify bridge
ports (for example, when you define VLANs), you must use the
lowest-numbered port in each trunk to represent the trunk. The
operation that you perform then applies to all ports in the trunk.
■
When you view information that applies to more than one port (for
example, bridging displays for trunks), the port number field
identifies all ports in the trunk. A VLAN summary display lists all
physical ports to indicate which physical system connectors can
receive or transmit frames within a VLAN. (Use the VLAN detail
display to see trunk port groups.)