Ip Dhcp Relay Information Option Vpn - Cisco Nexus 7000 Series Command Reference Manual

ip dhcp relay information option vpn

ip dhcp relay information option vpn
To enable VRF support for the DHCP relay agent, use the ip dhcp relay information option vpn command.
To disable VRF support, use the no form of this command.
ip dhcp relay information option vpn
no ip dhcp relay information option vpn
Syntax Description
This command has no arguments or keywords.
Command Default
By default, the device does not support forwarding of DHCP requests to DHCP servers in different VRFs
than the VRF that the DHCP client belongs to.
Command Modes
Global configuration
Command History
Release
5.0(2)
Usage Guidelines
To use this command, you must enable Option-82 information insertion for the DHCP relay agent (see the ip
dhcp relay information option command).
You can configure the DHCP relay agent to forward DHCP broadcast messages from clients in one VRF to
DHCP servers in a different VRF. By using a single DHCP server to provide DHCP support to clients in
multiple VRFs, you can conserve IP addresses by using a single IP address pool rather than one for each VRF.
If a DHCP request arrives on an interface that you have configured with a DHCP relay address and VRF
information and the address of the DCHP server belongs to a network on an interface that is a member of a
different VRF, the device inserts Option-82 information in the request and forwards it to the DHCP server in
the server VRF. The Option-82 information that the devices adds to a DHCP request relayed to a different
VRF includes the following:
• VPN identifier—Contains the name of the VRF that the interface that receives the DHCP request is a
• Link selection—Contains the subnet address of the interface that receives the DHCP request.
• Server identifier override—Contains the IP address of the interface that receives the DHCP request.
When the devices receives the DHCP response message, it strips off the Option-82 information and forwards
the response to the DHCP client in the client VRF.
This command does not require a license.
Cisco Nexus 7000 Series Security Command Reference
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member of.
Modification
This command was introduced.
I Commands