Example 2: One-Armed Routing Configuration - 3Com 4007 Implementation Manual

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Example 2: One-Armed Routing Configuration

Figure 20 shows a one-armed router configuration. (The switch fabric
module resides in slot 7 but is logically represented above the other
modules.)
In this configuration:
There are three Layer 2 modules, a Multilayer Switching Module, and
the switch fabric module.
There are four VLANs:
VLAN1, the default VLAN on all modules (tagged on the
front-panel and backplane ports of the Layer 2 modules and on the
corresponding switch fabric module ports). The default VLAN is not
represented in the figure.
VLAN2, a port-based VLAN that is defined on the Layer 2 modules
in slot 1 and slot 2. It is defined as a protocol-based VLAN for IP on
the Multilayer Switching Module in slot 4. The IP routing interface
for IP VLAN 2 (150.10.2.12) is defined to be on the same
subnetwork as the devices connected to the Layer 2 modules in
slots 1 and 2. (For example, a PC is defined as 150.10.2.1.)
VLAN3, a port-based VLAN that is defined on the Layer 2 module
in slot 2. It is defined as a protocol-based VLAN for IP on the
Layer 3 module in slot 4. The IP routing interface for IP VLAN 3
(150.10.3.12) is defined to be on the same subnetwork as the
devices that are connected to the Layer 2 module in slot 2.
VLAN4, a port-based VLAN that is defined on the Layer 2 module
in slot 3. It is defined as a protocol-based VLAN for IP on the
Layer 3 module in slot 4. The IP routing interface for IP VLAN 4
(150.10.4.12) is defined to be on the same subnetwork as the
devices that are connected to the Layer 2 module in slot 3.
On the Multilayer Switching Module, the backplane port 13 is part of
all four VLANs and is tagged in all four. IP routing is enabled with RIP.