Dell Configuration Guide for the S4048–ON System 9.14.2.6

Proxy Gateway with VRRP

VLT proxy gateway solves the inefficient traffic trombone problem when VLANs are extended between date centers and when VMs are migrated between the two DCs. Starting from Dell EMC Networking OS 9.14.0.0, VRRP provides a much simpler method to solve the traffic trombone problem.

This is achieved by configuring same VRRP group IDs to the extended L3 VLANs and VRRP stays active-active across all four VLT nodes even though they are in two different VLT domains.

The following illustration shows a sample configuration with two data centers:

• Server racks, Rack 1 and Rack 2, are part of data centers DC1 and DC2, respectively.
• Rack 1 is connected to devices A1 and B1 in a Layer 2 network segment.
• Rack 2 is connected to devices A2 and B2 in a Layer 2 network segment.
• A VLT link aggregation group (LAG) is present between A1 and B1 as well as A2 and B2.
• A1 and B1 are connected to core routers, C1 and D1 with VLT routing enabled.
• A2 and B2 are connected to core routers, C2 and D2, with VLT routing enabled.
• The core routers C1 and D1 in the local VLT domain are connected to the core routers C2 and D2 in the remote VLT Domain using VLT links.
• The core routers C1 and D1 in local VLT Domain along with C2 and D2 in the remote VLT Domain are part of a Layer 3 cloud.
• The core routers C1, D1, C2, D2 are in a VRRP group with the same vrrp-group ID.

When a virtual machine running in Server Rack 1 migrates to Server Rack 2, L3 packets for that VM are routed through the default gateway.

The following examples show sample configurations of the core routers.

Sample configuration of C1:

vlt domain 10 
 peer-link port-channel 128 
 back-up destination 10.16.140.6 
 system-mac mac-address 00:00:aa:00:00:00 
 unit-id 0 
 peer-routing 


interface port-channel 128
channel member ten 1/1/1
channel member ten 1/1/2
no shutdown


int ten 1/5/1
port-channel-protocol lacp
port-channel 10 mode active
no shut

int ten 1/4/1
port-channel-protocol lacp
port-channel 20 mode active
no shut

interface port-channel 10
vlt-peer-lag po 10
switchport
no shutdown

interface port-channel 20
vlt-peer-lag po 20
switchport
no shutdown

int vlan 100
ip address 100.1.1.1/24
tagged port-channel 10
vrrp-group 10
advertise-interval 60
virtual-ip 100.1.1.254
priority 100
no shutdown


int vlan 200
tagged port-channel 20
no shutdown


router ospf 10
network 100.1.1.0/24 area 0 

Sample configuration of D1:

vlt domain 10 
 peer-link port-channel 128 
 back-up destination 10.16.140.5 
 system-mac mac-address 00:00:aa:00:00:00 
 unit-id 1 
 peer-routing 


interface port-channel 128
channel member ten 1/1/1
channel member ten 1/1/2
no shutdown


int ten 1/5/1
port-channel-protocol lacp
port-channel 10 mode active
no shut

int ten 1/4/1
port-channel-protocol lacp
port-channel 20 mode active
no shut

interface port-channel 10
vlt-peer-lag po 10
switchport
no shutdown

interface port-channel 20
vlt-peer-lag po 20
switchport
no shutdown

int vlan 100
ip address 100.1.1.2/24
tagged port-channel 10
vrrp-group 10
advertise-interval 60
virtual-ip 100.1.1.254
priority 100
no shutdown


int vlan 200
tagged port-channel 20
no shutdown


router ospf 10
network 100.1.1.0/24 area 0 

Sample configuration of C2:

vlt domain 10 
 peer-link port-channel 128 
 back-up destination 10.16.140.4 
 system-mac mac-address 00:00:aa:00:00:cc 
 unit-id 1 
 peer-routing 


interface port-channel 128
channel member ten 1/1/1
channel member ten 1/1/2
no shutdown


int ten 1/5/1
port-channel-protocol lacp
port-channel 10 mode active
no shut

int ten 1/4/1
port-channel-protocol lacp
port-channel 20 mode active
no shut

interface port-channel 10
vlt-peer-lag po 10
switchport
no shutdown

interface port-channel 20
vlt-peer-lag po 20
switchport
no shutdown

int vlan 100
ip address 100.1.1.3/24
tagged port-channel 10
vrrp-group 10
advertise-interval 60
virtual-ip 100.1.1.254
priority 100
no shutdown


int vlan 200
tagged port-channel 20
no shutdown


router ospf 10
network 100.1.1.0/24 area 0 

Sample configuration of D2:

vlt domain 10 
 peer-link port-channel 128 
 back-up destination 10.16.140.3 
 system-mac mac-address 00:00:aa:00:00:cc 
 unit-id 1 
 peer-routing 


interface port-channel 128
channel member ten 1/1/1
channel member ten 1/1/2
no shutdown


int ten 1/5/1
port-channel-protocol lacp
port-channel 10 mode active
no shut

int ten 1/4/1
port-channel-protocol lacp
port-channel 20 mode active
no shut

interface port-channel 10
vlt-peer-lag po 10
switchport
no shutdown

interface port-channel 20
vlt-peer-lag po 20
switchport
no shutdown

int vlan 100
ip address 100.1.1.4/24
tagged port-channel 10
vrrp-group 10
advertise-interval 60
virtual-ip 100.1.1.254
priority 100
no shutdown


int vlan 200
tagged port-channel 20
no shutdown


router ospf 10
network 100.1.1.0/24 area 0