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9.3 Other declarations
9.3.1 Reject
reject
ip-addres
s;
The
reject
statement causes the DHCP client to reject offers from servers who use the specified address
as a server identifier. This can be used to avoid being configured by rogue or misconfigured dhcp
servers, although it should be a last resort - better to track down the bad DHCP server and fix it.
9.3.2 Interface
interface "
nam
e" {
declarations
... }
A client with more than one network interface may require different behaviour depending on which
interface is being configured. All timing parameters and declarations other than lease and alias
declarations can be enclosed in an interface declaration, and those parameters will then be used only for
the interface that matches the specified name. Interfaces for which there is no interface declaration will
use the parameters declared outside of any interface declaration, or the default settings
9.4 DHCP Options
The DHCP client supports only a subset of configuration options specified in [3]. However, this
mechanism is extensible, allowing vendor-specific customization and possible support of more options
in future. A DHCP client accepts the following information and uses it to configure the IP stack:
IP address
Subnet mask
The following would be useful, but are not supported in current software:
Default routers (one only)
Static routes
These are less useful but it is possible they will be supported in future:
IP forwarding enable/disable
Default IP time-to-live (TTL)
Interface Maximum Transmission Unit (MTU)
Host name
The following are not configurable in the current IP core and are unlikely to be supported:
Non-local source routing enable/disable
Policy filters for non-local source routing
Maximum re-assembly size
Path MTU ageing timeout
MTU plateau table
All-subnets-MTU
Broadcast address flavour
Perform mask discovery
Be a mask supplier
Perform router discovery
Router solicitation address
Trailer encapsulation
ARP cache timeout
Ethernet encapsulation
Default TCP TTL
TCP keep-alive interval
TCP keep-alive data size
The following documentation, adapted from manual pages provided by the Internet Software
Consortium, gives the format of allowed DHCP options which may be specified in the configuration file.
