Manual Allocation; Lease Options - Novell NETWARE 6-DOCUMENTATION Manual

Manual Allocation

Lease Options

Use Manual or static allocation to assign addresses to DHCP or BOOTP
clients using the DNS/DHCP Management Utility. A specific IP address is
assigned to the client based on an identifier such as the client's hardware or
MAC address.
Manual allocation of DHCP eliminates the error-prone method of manually
configuring hosts with IP addresses in networks for which IP address
management without DHCP is desired. Manual allocation can be permanent
or set to expire at a future time. When you manually allocate addresses, you
can also create corresponding DNS Resource Records, thereby eliminating
another error-prone activity.
A client acquires a lease for a fixed period of time. The length of the lease
could be a number of hours or days, or it could be for an indefinite period.
After a lease for an IP address has been granted, a client can issue a request to
extend its lease. The client can also issue a message to the server to release the
address back to the server when the address is no longer required.
If a network has a scarcity of IP addresses and must reassign them, the DHCP
server will reassign an address when the lease has expired. The server uses
configuration information to choose addresses to reuse. For example, the
server might choose the least recently assigned address for reassignment.
After receiving an address assignment, the host determines whether the
address is in use by another host before accepting the address.
IMPORTANT:
Address duplication sometimes occurs with Windows 95 clients. If
a Windows 95 client receives a response indicating that the assigned address is in
use by another device, a message indicates the IP address conflict. However, the
client does not send a DHCPDECLINE message as required by RFC 1534, section
4.4.1.
To minimize the chance of address duplication, the DHCP server can be
configured to ping an address to test its validity before assigning it to a host.
If the server receives a response from another device (indicating ownership of
the address), the current address assignment is withdrawn so that another
address can be assigned to the host.
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Understanding