Kerio Tech Firewall6 - Manual (Page 116)

Chapter 8 Configuration of network services
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1. Data about expired and released addresses are kept by the DHCP server and can
be used later if the same client demands a lease. If free IP addresses are lacked,
these addresses can be leased to other clients.
2. Declined addresses are handled according to the settings in the Options tab (see
below).
The following columns are hidden by default (for details on showing and hiding columns, see
chapter 3.2 ):
• Last Request Time — date and time when the recent request for a lease or lease exten-
sion was sent by a client
• Lease Remaining Time — time remaining until the appropriate Lease Expiration
Use the Release button to release a selected IP address immediately (independently of its sta-
tus). Released addresses are considered free and can be assigned to other clients immediately.
Click on the Reserve button to reserve a selected (dynamically assigned) IP address based on
the MAC address or name of the host that the address is currently assigned to. The Scopes tab
with a dialog where the appropriate address can be leased will be opened automatically. All
entries except for the Description item will be already defined with appropriate data. Define
the Description entry and click on the OK button to assign a persistent lease for the IP address
of the host to which it has been assigned dynamically.
Note: The MAC address of the host for which the IP is leased will be inserted to the lease
reservation dialog automatically. To reserve an IP address for a hostname, change settings of
the Reservation For and Value items.
DHCP server — advanced options
Other DHCP server parameters can be set in the Options tab.
BOOTP
If this option is enabled, the DHCP server will assign IP addresses (including optional pa-
rameters) also to clients of BOOTP protocol (protocol used formerly to DHCP— it assigns
configurations statically only, according to MAC addresses).
Windows RAS
Through this option you can enable DHCP service for RAS clients (Remote Access Service).
You can also specify time when the service will be available to RAS clients (an IP address
will be assigned) if the default value is not convenient.