2 declarations – Heritage Kayaks Heritage Series User Manual

Page 127

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122

DHCP Server Operation

on which the client is booting. If it doesn’t find any such entry, it then tries
to find an entry which has no fixed-address parameter. If no such entry is
found, then DHCP acts as if there is no entry in the

dhcpd.conf

file for that

client, even if there is an entry for that client on a different subnet or shared
network.

8.4.2 Declarations

Subnet

subnet

subnet-number

netmask

netmask

{

[

parameters

]

[

declarations

]

}

The

subnet

statement is used to provide the DHCP server with enough

information to determine whether or not an IP address is on that subnet.
It may also be used to provide subnet-specific parameters and to specify
what addresses may be dynamically allocated to clients booting on that
subnet. Such addresses are specified using the

range

declaration.

subnet-number

should be an IP address which resolves to the subnet

number of the subnet being described. The

netmask

should be an IP address

which resolves to the subnet mask of the subnet being described. The
subnet number, together with the subnet mask, are sufficient to determine
whether any given IP address is on the specified subnet.
Although a subnet mask must be given with every subnet declaration, it is
recommended that if there is any variance in subnet masks at a site, a

subnet-mask

option statement be used in each

subnet

declaration to set the

desired subnet mask; any

subnet-mask

option statement will override the

subnet mask declared in the

subnet

statement.


Range

range [ dynamic-bootp ] low-address [ high-address ];

For any subnet on which addresses will be assigned dynamically, there
must be at least one

range

statement. The range statement gives the lowest

and highest IP addresses in a range. All IP addresses in the range should be
in the subnet in which the

range

statement is declared. The

dynamic-bootp

flag may be specified if addresses in the specified range may be
dynamically assigned to BOOTP clients as well as DHCP clients. When
specifying a single address,

high-address

can be omitted.


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