Deployment Guide

IPv4 Routing | 667
Parameters
Defaults
Not configured.
Command Modes
INTERFACE
Command
History
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.
Dell Networking OS 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 Dell Networking OS forwards to the
client with source port=67, destination port=68.
ip helper-address hop-count disable
c e s
Disable the hop-count increment for the DHCP relay agent.
Syntax
ip helper-address hop-count disable
To reenable the hop-count increment, use the no ip helper-address hop-count disable
command.
Defaults
Enabled; the hops field in the DHCP message header is incremented by default
Command Modes
CONFIGURATION
Command
History
Usage
Information
This command disables the incrementing of the hops field when boot requests are relayed to a DHCP
server through Dell Networking OS. If the incoming boot request already has a non-zero hops field, the
message will be relayed with the same value for hops. However, the message will be discarded if the
hops field exceeds 16, to comply with the relay agent behavior specified in RFC 1542.
ip-address
Enter an IP address in dotted decimal format (A.B.C.D).
default-vrf
(Optional) E-Series and C-Series Only: Enter default-vrf for the DHCP server
VRF is using.
Version 8.1.1.0 Introduced on E-Series ExaScale
Version 7.9.1.0 Introduced VRF on the E-Series
Version 7.6.1.0 Added support for S-Series
Version 7.5.1.0 Added support for C-Series
pre-Version 6.2.1.1 Introduced on E-Series
Version 8.1.1.0 Introduced on E-Series ExaScale
Version 7.6.1.0 Added support for S-Series
Version 7.5.1.0 Added support for C-Series
Version 6.3.1.0 Introduced for E-Series