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If the primary peer fails, the secondary peer (with the higher priority) takes the primary role. If the primary peer (with the
lower priority) later comes back online, it is assigned the secondary role (there is no preemption).
3. (Optional) When you create a VLT domain on a switch, Dell EMC Networking OS automatically creates a VLT-system MAC
address used for internal system operations.
VLT DOMAIN CONFIGURATION mode
system-mac mac-address mac-address
To explicitly configure the default MAC address for the domain by entering a new MAC address, use the system-mac
command. The format is aaaa.bbbb.cccc.
Also, reconfigure the same MAC address on the VLT peer switch.
Use this command to minimize the time required for the VLT system to synchronize the default MAC address of the VLT
domain on both peer switches when one peer switch reboots.
4. (Optional) When you create a VLT domain on a switch, Dell EMC Networking OS automatically assigns a unique unit ID (0 or
1) to each peer switch.
VLT DOMAIN CONFIGURATION mode
unit-id {0 | 1}
To explicitly configure the default values on each peer switch, use the unit-id command.
Configure a different unit ID (0 or 1) on each peer switch.
Unit IDs are used for internal system operations.
Use this command to minimize the time required for the VLT system to determine the unit ID assigned to each peer switch
when one peer switch reboots.
Connecting a VLT Domain to an Attached Access Device (Switch or Server)
To connect a VLT domain to an attached access device, use the following commands.
On a VLT peer switch: To connect to an attached device, configure the same port channel ID number on each peer switch in
the VLT domain.
1. Configure the same port channel to be used to connect to an attached device and enter interface configuration mode.
CONFIGURATION mode
interface port-channel id-number
2. Remove an IP address from the interface.
INTERFACE PORT-CHANNEL mode
no ip address
3. Place the interface in Layer 2 mode.
INTERFACE PORT-CHANNEL mode
switchport
4. Add one or more port interfaces to the port channel.
INTERFACE PORT-CHANNEL mode
channel-member interface
interface: specify one of the following interface types:
● For a 10-Gigabit Ethernet interface, enter the keyword TenGigabitEthernet then the slot/port information.
● For a 40-Gigabit Ethernet interface, enter the keyword fortyGigE then the slot/port information.
5. Ensure that the port channel is active.
INTERFACE PORT-CHANNEL mode
no shutdown
6. Associate the port channel to the corresponding port channel in the VLT peer for the VLT connection to an attached device.
INTERFACE PORT-CHANNEL mode
vlt-peer-lag port-channel id-number
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: To connect to the VLT domain and add port channels to it, configure a port channel. For
an example of how to verify the port-channel configuration, refer to VLT Sample Configuration.
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Virtual Link Trunking (VLT)