Administrator Guide

Proxy ARP is enabled only if peer routing is enabled on both the VLT peers. If you disable peer routing by
using the no peer-routingcommand in VLT DOMAIN node, a notification is sent to the VLT peer to disable
the proxy ARP. If peer routing is disabled when ICL link is down, a notification is not sent to the VLT peer and
in such a case, the VLT peer does not disable the proxy ARP operation.
When the VLT domain is removed on one of the VLT nodes, the peer routing configuration removal will be
notified to the peer. In this case VLT peer node disables the proxy ARP. When the ICL link is removed on one
of the VLT nodes by using the no peer-link command, the ICL down event is triggered on the other VLT
node, which in turn starts the proxy ARP application. The VLT node, where the ICL link is deleted, flushes the
peer IP addresses and does not perform proxy ARP for the additional LAG hashed ARP requests.
Configuring VLAN-Stack over VLT
To configure VLAN-stack over VLT, follow these steps.
1 Configure the VLT LAG as VLAN-stack access or trunk mode on both the peers.
INTERFACE PORT-CHANNEL mode
vlan-stack {access | trunk}
2 Configure VLAN as VLAN-stack compatible on both the peers.
INTERFACE VLAN mode
vlan-stack compatible
3 Add the VLT LAG as a member to the VLAN-stack on both the peers.
INTERFACE VLAN mode
member port-channel port—channel ID
4 Verify the VLAN-stack configurations.
EXEC Privilege
show running-config
Sample configuration of VLAN-stack over VLT (Peer 1)
Configure VLT domain
Dell(conf)#vlt domain 1
Dell(conf-vlt-domain)#peer-link port-channel 1
Dell(conf-vlt-domain)#back-up destination 10.16.151.116
Dell(conf-vlt-domain)#primary-priority 100
Dell(conf-vlt-domain)#system-mac mac-address 00:00:00:11:11:11
Dell(conf-vlt-domain)#unit-id 0
Dell(conf-vlt-domain)#
Dell#show running-config vlt
!
vlt domain 1
peer-link port-channel 1
back-up destination 10.16.151.116
primary-priority 100
system-mac mac-address 00:00:00:11:11:11
Virtual Link Trunking (VLT) 998