74
default-lease-time
tim
e;
Time
should be the length in seconds that will be assigned to a lease if the client requesting the lease does
not ask for a specific expiration time.
max-lease-time
max-lease-time
tim
e;
Time
should be the maximum length in seconds that will be assigned to a lease if the client requesting the
lease asks for a specific expiration time.
hardware
hardware
hardware-type hardware-addres
s;
In order for a BOOTP client to be recognized, its network hardware address must be declared using a
hardware
clause in the
host
statement.
hardware-type
must be the name of a physical hardware interface
type. Currently, only the ethernet and token-ring types are recognized. The
hardware-address
should be
a set of hexadecimal octets (numbers from 0 through ff) separated by colons. The
hardware
statement
may also be used for DHCP clients.
filename
filename "
filenam
e”;
The
filename
statement can be used to specify the name of the initial boot file which is to be loaded by a
client. The filename should be a filename recognizable to whatever file transfer protocol the client can be
expected to use to load the file.
server-name
server-name "
nam
e";
The
server-name
statement can be used to inform the client of the name of the server from which it is
booting.
Name
should be the name that will be provided to the client.
next-server
next-server
server-nam
e;
The next-server statement is used to specify the host address of the server from which the initial boot file
(specified in the filename statement) is to be loaded. Server-name should be a numeric IP address or a
domain name. If no next-server parameter applies to a given client, the DHCP server’s IP address is
used.
fixed-address
fixed-address
IP-address
[,
IP-address
... ];
The fixed-address statement is used to assign one or more fixed IP addresses to a client. It should only
appear in a
host
declaration. If more than one address is supplied, then when the client boots, it will be
assigned the address which corresponds to the network on which it is booting. If none of the addresses
in the
fixed-address
statement are on the network on which the client is booting, that client will not match
the
host
declaration containing that
fixed-address
statement.
dynamic-bootp-lease-cutoff
dynamic-bootp-lease-cutoff
dat
e;
The
dynamic-bootp-lease-cutoff
statement sets the ending time for all leases assigned dynamically to
BOOTP clients. Since BOOTP clients have no way of renewing leases, and do not know that their leases
could expire, the DHCP server assigns infinite leases to BOOTP clients. However, it may make sense in
some situations to set a cut-off date for all BOOTP leases.
Date
should be the date on which all assigned
BOOTP leases will end. The date is specified in the form
W YYYY/MM/DD HH:MM:SS
W is the day of the week expressed as a number from zero (Sunday) to six (Saturday). YYYY is the year,
including the century. MM is the month expressed as a number from 1 to 12. DD is the day of the month,
counting from 1. HH is the hour, from zero to 23. MM is the minute and SS is the second. The time is
assumed to be in Greenwich Mean Time (GMT), not local time.
If the system upon which DHCP will be operating does not support a real-time clock, then care should
be taken to specify a date which is 1,
January, 1970 (i.e. start of UNIX time) offset by the required BOOTP
lease duration. Clients and server(s) must agree on a common time and date (even if just from start of
UNIX time), otherwise this will not work correctly. If clients and servers cannot be guaranteed to share a
common notion of time and date, use
dynamic-bootp-lease-length
instead.
