User manual

Configuration through the web interface
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 Check that an IP address is not in use before offering it: When a DHCP
client requests a new IP address lease, before offering an IP address to that
client, use “ping” to test whether that IP address is already in use by another
host on the network but is unknown to the DHCP server. If an IP address is
determined to be in use, it is marked as Unavailable for a period of time, and it
will not be offered to any client while in this state. Enabling this test adds
approximately one second of delay before the IP address is offered to the client,
since the “ping” test must not receive a valid reply for that test to successfully
determine that the IP address is not already in use. This option is off (disabled)
by default. This option does not apply to Static Lease Reservations, since the
“ping” test is not used for them.
 Static Lease Reservations: A static lease reservation is a specific IP address
paired with a client's MAC address, which reserves the IP address for that
client's use only. This assures that a client always receives a lease for the same
IP address and that no other client obtains a lease for that address.
To add a reservation, enter the IP Address and MAC Address values, check or
clear the Enable checkbox, and then press the Add button.
After adding a reservation, you may click on the IP address or MAC address of
that entry in the table, permitting you to specify or modify the lease duration for
this reservation.
The Enable checkbox for the entry permits a reservation to be disabled without
actually removing the entry, then enabled again at a later time.
The Remove link is used to permanently remove a reservation from the DHCP
server configuration.
The Remove All link is used to permanently remove all reservations from the
DHCP server configuration.