Ip Pools - D-Link NetDefend DFL-210 User Manual

5.5. IP Pools

5.5. IP Pools
Overview
IP pools are used to offer other subsystems access to a cache of DHCP IP addresses. These
addresses are gathered into a pool by internally maintaining a series of DHCP clients (one per IP).
The DHCP servers used by a pool can either be external or be DHCP servers defined in
NetDefendOS itself. External DHCP servers can be specified as the server on a specific interface or
by a unique IP address. Multiple IP Pools can be set up with different identifying names.
The primary usage of IP Pools is with IKE Config Mode which is a feature used for allocating IP
addresses to remote clients connecting through IPsec tunnels. For more information on this see
Section 9.4.3, "Roaming Clients".
Basic IP Pool Options
The basic options available for an IP Pool are:
DHCP Server behind interface
Server filter
Specify DHCP Server Address
Client IP filter
Advanced IP Pool Options
Advanced options available for IP Pool configuration are:
Routing Table
Receive Interface
MAC Range
Indicates that the IP pool should use the DHCP server(s)
residing on the specified interface.
Optional setting used to specify which servers to use. If
unspecified any DHCP server on the interface will be used.
The order of the provided address or ranges (if multiple) will
be used to indicate the preferred servers.
Specify DHCP server IP(s) in preferred ascending order to be
used. Using the IP loopback address 127.0.0.1 indicates that
the DHCP server is NetDefendOS itself.
Optional setting used to specify which offered IPs are valid to
use. In most cases this will be set to the default of all-nets.
Alternatively a set of IP ranges might be specified. The filter
ensures that only certain IP addresses from DHCP servers are
acceptable and is used in the situation where there might be a
DHCP server response with an unacceptable IP address.
The routing table to be used for lookups when resolving the destination
interfaces for the configured DHCP servers.
A "simulated" virtual DHCP server receiving interface. This setting is
used to simulate a receiving interface when an IP pool is obtaining IP
addresses from internal DHCP servers. This is needed since the filtering
criteria of a DHCP server includes a Receive Interface.
An internal DHCP server cannot receive requests from the IP pool
subsystem on an interface since both the server and the pool are internal
to NetDefendOS. This setting allows such requests from a pool to
appear as though they come from a particular interface so that the
relevant DHCP server will respond.
A range of MAC addresses that will be use to create "fake" DHCP
clients. Used when the DHCP server(s) map clients by the MAC
address. An indication of the need for MAC ranges is when the DHCP
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Chapter 5. DHCP Services