Users Guide

VLAN Stacking

With the virtual local area network (VLAN)-stacking feature (also called stackable VLANs and QinQ), you can “stack” VLANs into one

tunnel and switch them through the network transparently.

For more information about basic VLAN commands, refer to the Virtual LAN (VLAN) Commands section in the Layer 2 chapter.

Important Points to Remember

• If you do not enable the spanning tree protocol (STP) across the stackable VLAN network, STP bridge protocol data units (BPDUs)

from the customer’s networks are tunneled across the stackable VLAN network.

• If you do enable STP across the stackable VLAN network, STP BPDUs from the customer’s networks are consumed and not tunneled

across the stackable VLAN network unless you enable protocol tunneling.

• Layer 3 protocols are not supported on a stackable VLAN network.

• Assigning an IP address to a stackable VLAN is supported when all the members are only stackable VLAN trunk ports. IP addresses on

a stackable VLAN-enabled VLAN are not supported if the VLAN contains stackable VLAN access ports. This facility is provided for the

simple network management protocol (SNMP) management over a stackable VLAN-enabled VLAN containing only stackable VLAN

trunk interfaces. Layer 3 routing protocols on such a VLAN are not supported.

• Dell Networking OS recommends that you do not use the same MAC address, on dierent customer VLANs, on the same stackable

VLAN.

• Interfaces congured using stackable VLAN access or stackable VLAN trunk commands do not switch trac for the default VLAN.

These interfaces are switch trac only when they are added to a non-default VLAN.

Topics:

• dei enable

• dei honor

• dei mark

• member

• show interface dei-honor

• show interface dei-mark

• vlan-stack access

• vlan-stack compatible

• vlan-stack dot1p-mapping

• vlan-stack protocol-type

• vlan-stack trunk

dei enable

Make packets eligible for dropping based on their drop eligible indicator (DEI) value.

Syntax

dei enable

Defaults Packets are colored green; no packets are dropped.

Command Modes CONFIGURATION

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