Users Guide

Version Description
8.1.1.0 Introduced on the E-Series ExaScale.
7.9.1.0 Introduced VRF on the E-Series.
7.6.1.0 Introduced on the S-Series.
7.5.1.0 Introduced on the C-Series.
6.2.1.1 Introduced on the E-Series.
Usage
Information
You can add multiple DHCP servers by entering the ip helper-address command multiple times. If
multiple servers are defined, an incoming request is sent simultaneously to all configured servers and the
reply is forwarded to the DHCP client.
The system uses standard DHCP ports, that is UDP ports 67 (server) and 68 (client) for DHCP relay
services. It listens on port 67 and if it receives a broadcast, the software converts it to unicast, and
forwards to it to the DHCP-server with source port=68 and destination port=67.
The server replies with source port=67, destination port=67 and the system forwards to the client with
source port=67, destination port=68.
ipv6 helper-address
Configures the IPv6 DHCP helper addresses without VRF.
C9000 Series
Syntax
[no] ipv6 helper-address ipv6-address
To delete the ipv6 helper address, use the [no] ipv6 helper-address ipv6-address command.
Parameters
ipv6-address Enter the keywordipv6–address through which the server address can be
reached.
Default Disabled.
Command Modes INTERFACE
Command
History
This guide is platform-specific. For command information about other platforms, see the relevant Dell
Networking OS Command Line Reference Guide.
The following is a list of the Dell Networking OS version history for this command.
Version Description
9.9(0.0) Introduced on the C9010.
9.7(0.0) Introduced on the S4810, S4820T, S6000, S6000–ON, Z9000, and Z9500.
Usage
Information
Use this command on the interfaces where the DHCP clients are connected to forward the packets from
clients to DHCP server and vice-versa.
Example
Dell(conf-if-te-0/0)#ipv6 helper-address
X:X:X:X::X IPv6 helper address
614 Dynamic Host Configuration Protocol (DHCP)