Users Guide

Command Mode INTERFACE
Usage
Information
The DHCP server is supported only on L3 interfaces. After you configure an IP helper address, the
address forwards UDP broadcasts to the DHCP server. You can configure multiple helper addresses on
an interface by repeating the same command for each DHCP server address. The no version of this
command returns the value to the default. The client-facing and server-facing interfaces must be in the
same VRF.
Example (IPv4)
OS10(config)# interface eth 1/1/22
OS10(conf-if-eth1/1/22)# ip helper-address 20.1.1.1 vrf blue
Supported
Releases
10.2.0E or later
ipv6 helper-address
Configures a DHCPv6 server address.
Syntax
ipv6 helper-address ipv6-address [vrf vrf-name]
Parameters
● vrf vrf-name — (Optional) Enter the keyword vrf and then the name of the VRF through which
the host address can be reached.
● ipv6–address — Specify the DHCPv6 server address in the A::B format.
Defaults Disabled
Command Mode INTERFACE
Usage
Information
Use this command on interfaces to which DHCPv6 clients connect, to forward the packets between
IPv6 clients and a DHCPv6 server. After you configure an IPv6 helper address, the address forwards
UDP broadcasts from IPv6 clients to the DHCPv6 server. You can configure multiple helper addresses on
an interface by repeating the same command for each DHCPv6 server address. The no version of this
command deletes the IPv6 helper address.
Example
OS10(config)# interface ethernet 1/1/22
OS10(conf-if-eth1/1/22)# ipv6 helper-address 2001:db8:0:1:1:1:1:1 vrf
blue
Supported
Releases
10.4.1.0 or later
ip dhcp-relay information-option
Configures the system to enable the remote-id string in Option 82.
Syntax
ip dhcp-relay information-option
Parameters None.
Default Not configured
Command Mode CONFIGURATION, INTERFACE CONFIGURATION
Usage
Information
By default, option 82 is enabled globally. When option 82 is enabled globally, the relay agent adds the
client information to the packet and sends it to the server. When option 82 is disabled globally, the client
packets are sent to the server without option 82 information. When both global as well as interface
level option 82 configurations are present , the configuration to disable option 82 takes precedence. The
following table shows the option 82 status depending on the global and interface level configurations:
Table 10. Option 82 status
Global Level Interface Level Option 82 status
Enable Enable Adds option 82 information
to the packet.
226 System management