Wireless/Redundant Edge Services xl Module Management and Configuration Guide WS.02.xx and greater

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IP Services—IP Settings, DHCP, and DNS
DHCP Server
When you use network pools, you can also specify a range of excluded
addresses, which are addresses in a pool that the Wireless Edge Services xl
Module is not allowed to assign. Use the excluded addresses to protect IP
addresses on your network that you want to remain fixed, such as the IP
addresses of routers and DNS servers.
A host pool contains a single fixed IP address and is designated to a specific
device. When that device sends a DHCP request, the Wireless Edge Services
xl Module recognizes its MAC address (or client identifier) and assigns the
device the fixed IP address.
Use host pools for devices that require a dynamic address but also a stable
address that never changes. For example, certain devices should almost
always be given static addresses so that routes remain accurate, the network
design remains logical and consistent, and the traffic flow remains uninter-
rupted. Network servers, such as Remote Access Dial In User Service
(RADIUS) servers, need stable addresses so that other network devices, which
are configured to query those servers, always know where to reach them.
However, sometimes a device that needs a stable IP address is also required
to take a dynamic address from a DHCP server. You can configure the router
to assign a fixed DHCP address to this device.
Also, when you want to assign a permanent address to a particular host,
sometimes it is better to configure this address through a DHCP server, rather
than through whatever application is on the host. DHCP automatically tracks
addresses so that two devices are not inadvertently given the same address.
Creating a Network Pool. To create a network pool of IP addresses, com-
plete these steps:
1. Select Network Setup > DHCP Server > Configuration.