Port-Based Virtual LANs (VLANs) and GVRP

Port-Based Virtual LANs (Static VLANs)

IP Interfaces

There is a one-to-one relationship between a VLAN and an IP network inter- face. Since the VLAN is defined by a group of ports, the state (up/down) of those ports determines the state of the IP network interface associated with that VLAN. When a VLAN comes up because one or more of its ports is up, the IP interface for that VLAN is also activated. Likewise, when a VLAN is deactivated because all of its ports are down, the corresponding IP interface is also deactivated.

VLAN MAC Address

The Series 5300XL switches have one unique MAC address for all of their VLAN interfaces. You can send an 802.2 test packet to this MAC address to verify connectivity to the switch. Likewise, you can assign an IP address to the VLAN interface, and when you Ping that address, ARP will resolve the IP address to this single MAC address.

Port Trunks

When assigning a port trunk to a VLAN, all ports in the trunk are automatically assigned to the same VLAN. You cannot split trunk members across multiple VLANs. Also, a port trunk is tagged, untagged, or excluded from a VLAN in the same way as for individual, untrunked ports.

Port Monitoring

If you designate a port on the switch for network monitoring, this port will appear in the Port VLAN Assignment screen and can be configured as a member of any VLAN. For information on how broadcast, multicast, and unicast packets are tagged inside and outside of the VLAN to which the monitor port is assigned, see “VLAN-Related Problems” on page C-19.

VLAN Restrictions

A port must be a member of at least one VLAN. In the factory default configuration, all ports are assigned to the default VLAN (DEFAULT_VLAN; VID = 1).

A port can be assigned to several VLANs, but only one of those assign­ ments can be untagged. (The “Untagged” designation enables VLAN oper­ ation with non 802.1Q-compliant devices.)

An external router must be used to communicate between tagged VLANs on the switch.

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