User's Manual

EnRoute50x/51x User’s Guide

TR0153 Rev. D2

Figure 37. DHCP relay settings for use with a centralized DHCP server

10.2.2 Configuring the Central DHCP Server

Guidelines for configuring the central DHCP server are provided below. The full configuration

of the central DHCP server will depend on the type of DHCP server that is used and is beyond

the scope of this document.

Typically the following information must be available in order to configure the server:

1. The local interface (to the DHCP server) over which the DHCP-related messages from

the mesh cluster arrive

2. The parameter(s) that define the address lease time

3. Whether DNS and domain names are to be provided by the DHCP server to clients

4. The range of the flat IP address that is used for assigning IP addresses to clients. The

range must not include the IP addresses set aside for the client interfaces on each

mesh node.

The following is a segment of the dhcpd.conf file for a Linux DHCP server (ISC DHCP server)

that illustrates the scope settings for the mesh network:

subnet 192.168.5.0 netmask 255.255.255.0

{

option broadcast-address 192.168.5.255;

option subnet-mask 255.255.255.0;

option domain-name "domain.com";

range 192.168.5.18 192.168.5.254;

}

Note that in this definition no “routers” option is needed. If a global “routers” option is defined, it

will be set to the correct value for proper operation inside the mesh network. In this example,