Configuring Advanced Features

Port-Based Virtual LANs (Static VLANs)

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.

Duplicate MAC addresses on different VLANs are not supported and can cause VLAN operating problems. These duplicates are possible and com- mon in situations involving Sun workstations with multiple network interface cards, with DECnet routers, and with certain Hewlett-Packard routers using OS versions earlier than A.09.70 where any of the following are enabled:

IPX

IP Host-Only

STP

XNS

DECnet

Currently, the problem of duplicate MAC addresses in IPX and IP Host- Only environments is addressed through the HP router OS version described under “HP Router Requirements” on page 9-76.However, for XNS and DECnet environments, a satisfactory solution is not available from any vendor at this time.

N o t e

Operating problems associated with duplicate MAC addresses are likely to

 

occur in VLAN environments where XNS and DECnet are used. For this

 

reason, using VLANs in XNS and DECnet environments is not currently

 

supported.

 

Before you can delete a VLAN, you must first re-assign all ports in the

 

 

VLAN to another VLAN.

Features

Advanced Configuring

 

 

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