Users Guide

ip dhcp-relay server-override
Enables server identifier override (suboption-11) globally on the relay agent.
Syntax
ip dhcp-relay server-override
Parameters None.
Defaults Disabled on the relay agent.
Command Mode CONFIGURATION
Usage
Information
Enabling the server identifier option on the relay agent allows the DHCP relay agent to act as the proxy
DHCP server such that the renew requests from the clients come to the relay agent rather than the
DHCP server directly.
Enabling the CLI at global level enables the server-override option on all the DHCP client-facing interfaces
by default. In order to disable the server-override option for specific client facing interfaces, configure no
ip dhcp-relay server-override command on them.
NOTE: Option-82 must be enabled Globally and at the interface level to activate the server-override
feature support.
This command is restricted to netadmin and sysadmin role users.
Example
OS10(conf)# ip dhcp-relay server-override
Supported
Releases
10.5.2 or later
ip dhcp-relay source-interface
Configures the DHCP relay source interface to be used by the DHCP relay agents to forward the packets to and from the DHCP
server.
Syntax
ip dhcp-relay {source-interface [ethernet node/slot/port | loopback
loopback-id | port-channel id-number | vlan vlan-id | virtual-network vn-
id]
Parameters
● ethernet node/ slot/port - Enter the ethernet interface type.
● loopback loopback-id - Enter the Loopback interface type.
● port-channel id-number - Enter the port channel interface type.
● vlan vlan-id - Enter the VLAN interface type.
● virtual-network vn-id - Enter the virtual network type.
Defaults No source-interface configuration on the interface and the client connected interface IP address is used
by the relay for forwarding.
Command Mode INTERFACE CONFIGURATION
Usage
Information
When you configure the DHCP-relay source interface on a given DHCP client facing interface, the DHCP
server uses the IP address of that source interface as the destination for the RELAY-REPLY packets.
This interface level source-interface configuration takes precedence over the VRF source-interface
configuration, if configured. The source-interface IP address takes precedence for the giaddr field even
if an interface IP address or virtual anycast gateway IP address is present on the interface.
You can configure the source-interface on all types of DHCP client interfaces (Ethernet interface, port-
channel, VLAN, and virtual-network).
NOTE: You must enable the link-selection option Globally to allocate the IP address on the client
subnet if the client-connected interface IP address and source interface IP address are in different
network domains.
This command is restricted to netadmin and sysadmin role users.
320 System management