RFC 3397 (rfc3397) - Page 2 of 8
Dynamic Host Configuration Protocol (DHCP) Domain Search Option
Alternative Format: Original Text Document
RFC 3397 DHCP Domain Search Option November 2002
1. Introduction
The Dynamic Host Configuration Protocol (DHCP) [RFC 2131] provides a
mechanism for host configuration. [RFC 2132] and [RFC 2937] allow DHCP
servers to pass name service configuration information to DHCP
clients. In some circumstances, it is useful for the DHCP client to
be configured with the domain search list. This document defines a
new DHCP option which is passed from the DHCP Server to the DHCP
Client to specify the domain search list used when resolving
hostnames with DNS. This option applies only to DNS and does not
apply to other name resolution mechanisms.
1.1. Terminology
This document uses the following terms:
DHCP client
A DHCP client or "client" is an Internet host using DHCP to
obtain configuration parameters such as a network address.
DHCP server
A DHCP server or "server" is an Internet host that returns
configuration parameters to DHCP clients.
1.2. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in "Key words for use in
RFCs to Indicate Requirement Levels" [RFC 2119].
2. Domain Search Option Format
The code for this option is 119.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 119 | Len | Searchstring...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Searchstring...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
In the above diagram, Searchstring is a string specifying the
searchlist. If the length of the searchlist exceeds the maximum
permissible within a single option (255 octets), then multiple
options MAY be used, as described in "Encoding Long Options in the
Dynamic Host Configuration Protocol (DHCPv4)" [RFC 3396].
Aboba & Cheshire Standards Track