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How to set up Virtual Link Trunking (VLT) on Dell Networking OS9 Switches

Summary: The steps in this article are applicable to Dell Networking OS9 switches that support Virtual Link Trunking.

This article applies to This article does not apply to This article is not tied to any specific product. Not all product versions are identified in this article.
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Instructions

This article explains how to set up Virtual Link Trunking (VLT) on Dell Networking OS9 switches.

The steps in this article are applicable to Force 10 switches that support VLT. This article does not contain the requirements for VLT. It is recommended to verify the requirements for VLT before implementing these steps. Configuration guides can be found on the Dell Networking OS9 Documentation page for the applicable switch model and firmware version.

VLT Configuration Overview

Optional not required but preferred: Configuring Rapid Spanning-tree Protocol (RSTP) on the VLT peer switches

Command Purpose 
Force10# configure
 Enter configuration mode. 
Force10(conf)# protocol spanning-tree rstp
 Enter RSTP configuration mode. 
Force10(conf-rstp)# bridge-priority 4096 (primary peer)
Force10(conf-rstp)# bridge-priority 8192 (secondary peer)
 Optional: Configure RSTP bridge priority.*These priorities are not unique to the VLT pair and are used to show preference for the primary. Use a higher multiple of 4096 to avoid the primary becoming the root bridge. 
Force10(conf-rstp)# no disable
 Enable the spanning tree protocol.

Configure VLT interconnect for the VLT domain (a Static Lag between the VLT switches)

Command Purpose 
Force10# configure
 Enter configuration mode. 
Force10(conf)# interface range fortyGigE 0/56 , fortyGigE  0/60
 Enter interface configuration mode. Be aware of the spaces needed before and after the comma. 
Force10(conf-if-range-fo-0/56,fo-0/60)# no shutdown
 Enable the range of interfaces. 
Force10(conf-if-range-fo-0/56,fo-0/60)# interface port-channel 100
 Enter port channel configuration mode. 
Force10(conf-if-po-100)# channel-member fortyGigE  0/56,60
 Add the physical interface to the port channel. 
Force10(conf-if-po-100)# no shutdown
 Enable the port channel.
 
Warning: Do not add any VLANs to the VLT Interconnect (VLTi). The VLTi interface manages VLAN tagged or untagged traffic automatically between peers. Manually adding any VLAN configuration has been shown to disrupt traffic flow. If a VLAN configuration has been added to the VLTi, the recommended recovery procedure is as follows for both VLT members:
  1. Remove the VLAN configuration from the interface
  2. Save the configuration
  3. Reload the VLT member


Configure VLT Domain

Command Purpose 
Force10# configure
 Enter configuration mode. 
Force10(conf)# vlt domain 1
 Enter VLT domain configuration mode for domain ID 1-1000. 
Force10(conf-vlt-domain)# primary-priority 10 (primary peer)
Force10(conf-vlt-domain)# primary-priority 20 (secondary peer)
 Optional: Specify the VLT priority for each peer switch. 1-65535 (highest to lowest) 
Force10(conf-vlt-domain)# back-up destination 1.1.1.2 (primary peer)
Force10(conf-vlt-domain)# back-up destination 1.1.1.1 (secondary peer)
 Specify the management IP address of the peer switch. This sets up the Heartbeat that monitors the peer system status. 
Force10(conf-vlt-domain)# peer-link port-channel 100
 Associate the VLTi LAG to the VLT domain.
 
Note: When creating a VLT domain on a switch, Dell Networking OS9 automatically creates a VLT system MAC address used for the internal system operation. You can explicitly configure a default MAC address for the domain by entering a new MAC address. Use the system-mac command. 
Force10(conf-vlt-domain)# system-mac <mac-address>
Also, configure the same MAC address on the VLT peer switch. This command is used 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.

Configure the LACP LAG on both VLT Peers for the Connecting Device

Command Purpose 
Force10# configure
 Enter configuration mode 
Force10(conf)# interface tengigabit 0/20
 Enter interface configuration mode 
Force10(conf-if-te-0/20)# port-channel-protocol lacp
 Enter LACP configuration mode 
Force10(conf-if-te-0/20-lacp)# port-channel 20 mode active
 Set the port channel as "mode active" for LACP LAG 
Force10(conf-if-te-0/20-lacp)# interface port-channel 20
 Enter port channel configuration mode 
Force10(conf-if-po-20)# portmode hybrid
 Portmode hybrid allows the interface to pass tagged and untagged traffic. 
Force10(conf-if-po-20)# switchport
 Switchport puts the interface in layer 2 mode. 
Force10(conf-if-po-20)# vlt-peer-lag port-channel 20
 Assign the port channel as a VLT port channel 
Force10(conf-if-po-20)#end
 Exit configuration mode 
Force10# write
 Save configuration

 

Note: These steps should be repeated on both VLT peers. The devices connected across this LAG should be set up in a LACP LAG. The device is not aware it is connected to a VLT port channel, it performs like it is connected to a normal LACP port channel. 

Verifying and Monitoring

Verifying VLT Domain Status:

Primary VLT Peer: 
Force10# show vlt brief
VLT Domain Brief
-------------------------------------------------
Domain ID:                                                           1
Role:                                                                    Primary
Role Priority:                                                       10
ICL Link Status:                                                   Up
Heartbeat Status:                                                 Up
VLT Peer Status:                                                 Up
Local System MAC address:                          00:01:e8:8b:19:37
Remote System MAC address:                     00:01:e8:8b:18:b9
Configured System MAC address:               aa:11:22:33:44:55
Secondary VLT Peer: 
Force10# show vlt brief
VLT Domain Brief
-------------------------------------------------
Domain ID:                                                           1
Role:                                                                    Secondary
Role Priority:                                                        20
ICL Link Status:                                                   Up
Heartbeat Status:                                                 Up
VLT Peer Status:                                                 Up
Local System MAC address:                          00:01:e8:8b:18:b9
Remote System MAC address:                      00:01:e8:8b:19:37
Configured System MAC address:                aa:11:22:33:44:55
Verifying VLT PDUs and errors: 
Force10# show vlt statistics
-----------------------------------------------------
HeartBeat Messages Sent:                           95446
HeartBeat Messages Received:                   95440
ICL Hello's Sent:                                         95420
ICL Hello's Received:                                  95414
Domain Mismatch Errors:                              0
Version Mismatch Errors:                              0
Config Mismatch Errors:                                0
Verifying VLT Backup Link status:

Primary VLT peer: 
Force10# show vlt backup-link
VLT Backup Link
--------------------------------------------------
Destination:                                               1.1.1.2
Peer HeartBeat status:                               Up
HeartBeat Timer Interval:                           1
HeartBeat Timeout:                                    3
UDP Port:                                                  34998
HeartBeat Messages Sent:                         95305
HeartBeat Messages Received:                 95299
Secondary VLT peer: 
Force10# show vlt backup-link
VLT Backup Link
--------------------------------------------------
Destination:                                             1.1.1.1
Peer HeartBeat status:                             Up
HeartBeat Timer Interval:                         1
HeartBeat Timeout:                                  3
UDP Port:                                                34998
HeartBeat Messages Sent:                       95305
HeartBeat Messages Received:               95299
Verifying Matching configuration on both VLT Peers: 
Force10# show vlt mismatch

Affected Products

Equallogic PS6000s, FN IO Module, Force10 MXL Blade, Force10 S2410-01-10GE-24P, Force10 S2410-01-10GE-24CP, Force10 S25-01-GE-24P, Force10 S25-01-GE-24T, Force10 S50-01-GE-48T-V, Force10 S50-01-GE-48T, PowerSwitch S4810P, PowerSwitch S4820T , PowerSwitch S5000, Force10 S55T, Force10 S60-44T, PowerSwitch S6000, Dell Networking Z9500, Dell Networking S3100 Series, PowerSwitch S4048T-ON, PowerEdge FX2/FX2s ...

Products

S Series, OS9, Force10 S25N-S50N, Force10 S25-01-GE-24V, Force10 S50-01-GE-48T-V, Force10 S50-01-GE-48T, PowerSwitch S3048-ON, PowerSwitch S4048-ON, PowerSwitch S4810P, PowerSwitch S4810-ON, PowerSwitch S4820T, PowerSwitch S5000, Force10 S50P , Force10 S55T, Force10 S60-44T, PowerSwitch S6000, PowerSwitch S6000 ON, Force10 Z9000, PowerSwitch S4048T-ON, PowerSwitch S6010-ON, PowerSwitch S6100-ON, PowerSwitch Z9100-ON ...
Article Properties
Article Number: 000118094
Article Type: How To
Last Modified: 22 Mar 2024
Version:  5
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