User's Manual

EnRoute500 User’s Guide
TR0149 Rev. C5
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The IP address of the central DHCP server is set with the ‘dhcp.relay.server’ parameter in the
‘sys’ interface. The server must be reachable through the mesh gateway’s wired backhaul
interface. In the example below, the central DHCP server resides on a host on the same
segment to which the mesh gateway’s wired interface is connected.
> use sys
sys> set dhcp.relay.server=192.168.5.1
The external DHCP server address can be set via the web interface on the “DHCP Relay” sub-
tab under the “DHCP” tab on the “System Parameters” page (see Figure 37).
The address space that is to be used for the wireless clients is set with the
‘dhcp.relay.dhcp_subnet’ parameter in the ‘sys’ interface. This subnet can either be a class A
(/8), class B (/16), or class C (/24) network. The value must be specified in CIDR notatation (a
subnet and its size separated by a ‘/’) as shown in the example below.
> use sys
sys> set dhcp.relay.dhcp_subnet=192.168.5.0/24
Figure 37. DHCP relay settings for use with a centralized DHCP server
The address space used for the nodes’ DHCP clients can be set via the web interface on the
“DHCP Relay” sub-tab under the “DHCP” tab on the “System Parameters” page (see Figure
37).
The IP addresses of the client interfaces (eth0, wlan1-4) need to be assigned to each of the
nodes in the mesh cluster. This is done by defining a base value for the interfaces using the
‘dhcp.relay.base’ parameter in the ‘sys’ interface, which determines the address offset for each
individual node. The value must be in the range from 0 to 255 and is used to derive the per-
client relay agent address by OR-ing it with the value of the dhcp_subnet parameter. It is
recommended that the gateway in a mesh cluster be assigned the lowest available value (3 in
the example above) and the repeaters in the mesh cluster are given successively higher
values, with an increment of 5 between them. The example below shows the configuration for
a mesh cluster consisting of 3 nodes.