Users Guide

DHCP snooping in a VLT environment
OS10 supports DHCP snooping in a VLT environment. DHCP snooping switches in a VLT topology synchronize DHCP snooping binding
information between them. The system interprets the VLTi link between VLT peers as trusted interfaces. To configure DHCP snooping in
a VLT environment:
• Enable DHCP snooping on both VLT peers.
• Configure the VLT port-channel interfaces facing the DHCP server as trusted interfaces.
In the following VLT topology, AGG1 and AGG2 are VLT peers and have VLT port-channel interfaces connected to the VM server and
Core switch. The DHCP server is reachable through the CORE switch. The following describes the functioning of DHCP snooping in a VLT
environment:
• One of the VLT peers receives a DHCP client packet from a DHCP client on the VM server through the VLT port-channel interface.
The switch processes this packet.
• The VLT peer forwards the DHCP client packet to the Core switch through the VLT port-channel interface.
• The Core switch forwards the DHCP reply packet from the DHCP server to one of the VLT peers, which processes the packet.
• If the DHCP reply packet is from a trusted DHCP server, the VLT peer forwards the reply packet to the DHCP client on the VM
server.
• The VLT peers synchronize the DHCP snooping binding table.
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System management