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VLT Proxy Gateway
The Virtual link trucking (VLT) proxy gateway feature allows a VLT domain to locally terminate and route L3 packets that are destined
to a Layer 3 (L3) end point in another VLT domain. Enable the VLT proxy gateway using the link layer discover protocol (LLDP)
method or the static configuration. For more information, refer to
Dell Networking OS Command Line Reference Guide
.
Proxy Gateway in VLT Domains
Using a proxy gateway, the VLT peers in a domain can route the L3 packets destined for VLT peers in another domain as long as they
have L3 reachability for the IP destinations.
A proxy gateway in a VLT domain provides the following benefits:
•
Avoids sub-optimal routing of packets by a VLT domain when packets are destined to the endpoint in another VLT domain.
•
Provides resiliency if a VLT peer goes down by performing proxy routing for the peer’s destination MAC address in another VLT
domain.
A typical scenario is virtual movement of servers across data centers. Virtual movement enables live migration of running virtual
machines (VMs) from one host to another without downtime. For example, consider a square VLT connecting two data centers. If a
VM,
VM1
on Server Rack 1 has C as its default gateway and VM1 performs a virtual movement to Server Rack 2 with no change in
default gateway. In this case, L3 packets destined for C can be routed either by C1 or D1 locally. To do this, install the local system
mac address of C and D in both C1 and D1 so the packets for C and D could have a hit at C1 /D1 and be routed locally.
The following figure shows:
•
Server racks, named Rack 1 and Rack 2, are part of data centers named DC1 and DC2, respectively.
•
Rack 1 is connected to devices A and B in Layer 2.
•
Rack 2 is connected to devices A and B in Layer 2.
•
A VLT link aggregation group (LAG) is present between A and B.
•
A and B are connected to core routers, C and D.
•
VLT routing is present between C and D.
•
C1 and D1 are Layer 3 core routers in DC2, in which VLT routing is enabled.
•
The core routers C and D in the local VLT domain is connected to the core routers C1 and D1 in the remote VLT Domain using
VLT links in eVLT fashion.
For more information about eVLT, refer to the
chapter. The core or Layer 3 routers C and D in local VLT
Domain and C1 and D1 in the remote VLT Domain are then part of a Layer 3 cloud.
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VLT Proxy Gateway
Summary of Contents for S4048-ON
Page 1: ...Dell Configuration Guide for the S4048 ON System 9 9 0 0 ...
Page 146: ...Figure 14 BFD Three Way Handshake State Changes 146 Bidirectional Forwarding Detection BFD ...
Page 522: ...Figure 87 Configuring Interfaces for MSDP 522 Multicast Source Discovery Protocol MSDP ...
Page 523: ...Figure 88 Configuring OSPF and BGP for MSDP Multicast Source Discovery Protocol MSDP 523 ...
Page 528: ...Figure 91 MSDP Default Peer Scenario 1 528 Multicast Source Discovery Protocol MSDP ...
Page 529: ...Figure 92 MSDP Default Peer Scenario 2 Multicast Source Discovery Protocol MSDP 529 ...
Page 530: ...Figure 93 MSDP Default Peer Scenario 3 530 Multicast Source Discovery Protocol MSDP ...
Page 633: ...Policy based Routing PBR 633 ...
Page 777: ...Figure 119 Single and Double Tag TPID Match Service Provider Bridging 777 ...
Page 778: ...Figure 120 Single and Double Tag First byte TPID Match 778 Service Provider Bridging ...