Overlapping Vlans And Multi-Vlan Ports - Cisco WS-C2950-24 Configuration Manual

Chapter 8 Configuring VLANs

Overlapping VLANs and Multi-VLAN Ports

Caution
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A multi-VLAN port connected to a router can link two or more VLANs.
Intra-VLAN traffic stays within the boundaries of the respective VLANs as shown
in Figure 8-2. Connectivity between VLANs is through the router connected to
the multi-VLAN port.
A multi-VLAN port performs normal switching functions in all its assigned
VLANs. For example, when a multi-VLAN port receives an unknown Media
Access Control (MAC) address, all the VLANs to which the port belongs learn
the address. Multi-VLAN ports also respond to the STP messages generated by
the different instances of STP in each VLAN.
For the restrictions that apply to multi-VLAN ports, see the
Configuration Conflicts" section on page
Figure 8-2 Two VLANs Sharing a Port Connected to a Router
Ports in static-access
VLAN 77
Cisco router
To avoid unpredictable STP behavior and a loss of connectivity, do not connect
multi-VLAN ports to hubs or switches. Connect multi-VLAN ports to routers
or servers.
Catalyst 2900 Series XL and Catalyst 3500 Series XL Software Configuration Guide
Overlapping VLANs and Multi-VLAN Ports
9-2.
mode
VLAN 42
Port in multi-VLAN mode
"Avoiding
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