Static Virtual LANs (VLANs)

Port-Based Virtual LANs (Static VLANs)

Effect of VLANs on Other Switch Features

Spanning Tree Operation with VLANs

Because the switch follows the 802.1Q VLAN recommendation to use single- instance spanning tree, Spanning Tree operates across all ports on the switch (regardless of VLAN assignments) instead of on a per-VLAN basis. This means that if redundant physical links exist between the switch and another 802.1Q device, all but one link will be blocked, regardless of whether the redundant links are in separate VLANs. However, you can use port trunking to prevent Spanning Tree from unnecessarily blocking ports (and to improve overall network performance).

Note that Spanning Tree operates differently in different devices. For example, in the (obsolete, non-802.1Q) ProCurve Switch 2000 and the ProCurve Switch 800T, Spanning Tree operates on a per-VLAN basis, allowing redundant physical links as long as they are in separate 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 Addresses

Some switch models use the same MAC address for all configured VLANs, while other switch models use a different MAC address for each configured VLAN.

One (Same) MAC Address for all VLANs

Different MAC Address for Each VLAN

 

 

 

2600

2510/2510G

4100gl

2600-PWR

3400cl

6108

2610

5300xl

 

2610-PWR

6400cl

 

2810

 

 

2800

 

 

 

 

 

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