Reference Guide

Virtual Link Trunking (VLT) | 303
Use the peer-down-vlan parameter to configure the VLAN where a VLT peer will forward received packets
over the VLTi from an adjacent VLT peer that is down. When a VLT peer with BMP reboots, untagged
DHCP discover packets are sent to the peer over the VLTi. Using this configuration ensures the DHCP
discover packets are forwarded to the VLAN that has the DHCP server.
2 Remove an IP address from the interface.
no ip address
INTERFACE
PORT-CHANNEL
3 Place the interface in Layer 2 mode.
switchport
INTERFACE
PORT-CHANNEL
4 Add one or more port interfaces to the port channel.
interface specifies one of the following interface types:
1-Gigabit Ethernet: Enter
gigabitethernet slot/port.
10-Gigabit Ethernet: Enter
tengigabitethernet slot/port.
channel-member interface INTERFACE
PORT-CHANNEL
5 Ensure that the port channel is active.
no shutdown
INTERFACE
PORT-CHANNEL
6 Associate the port channel to the corresponding port
channel in the VLT peer for the VLT connection to an
attached device.
Valid port-channel ID numbers are from 1 to 128.
vlt-peer-lag port-channel
id-number
INTERFACE
PORT-CHANNEL
7 Repeat Steps 1 to 6 on the VLT peer switch to configure the same port channel as part of the VLT domain.
8 On an attached switch or server: Configure a port channel to connect to the VLT domain and add port channels
to it. Figure 22-12 shows how to verify the port-channel configuration.
(Optional) Configure a VLT VLAN peer-down
Step Task Command Syntax Command Mode
1 Enter VLT-domain configuration mode for a specified
VLT domain.
Range of domain IDs: 1 to 1000.
vlt domain domain-id
CONFIGURATION
2 Enter the port-channel number that will act as the
interconnect trunk.
Range: 1 to 128.
peer-link port-channel
id-number
VLT DOMAIN
CONFIGURATION
3 Enter the VLAN ID number of the VLAN where the
VLT forwards packets received on the VLTi from an
adjacent peer that is down.
Range: 1 to 4094.
peer-link port-channel
id-number peer-down-vlan
vlan interface number
VLT DOMAIN
CONFIGURATION
Connect a VLT domain to an attached access device (switch or server)
Step Task Command Syntax Command Mode