35ba231dc0
- Remove manpages patch and keep modified man pages as Source files
- Improve dhclient.8 man page to list options in a style consistent with
most other man pages on the planet
- Upgrade to latest dhcp LDAP patch, which brings in a new
dhcpd-conf-to-ldap script, updated schema file, and other bug fixes
including SSL support for LDAP authentication (#375711)
- Do not run dhcpd and dhcrelay services by default (#362321)
661 lines
25 KiB
Groff
661 lines
25 KiB
Groff
.\" $Id: dhclient.conf.5,v 1.17.84.2 2007/05/23 23:30:32 each Exp $
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.\"
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.\" Copyright (c) 2004,2007 by Internet Systems Consortium, Inc. ("ISC")
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.\" Copyright (c) 1996-2003 by Internet Software Consortium
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.\"
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.\" Permission to use, copy, modify, and distribute this software for any
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.\" purpose with or without fee is hereby granted, provided that the above
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.\" copyright notice and this permission notice appear in all copies.
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.\"
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.\" THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
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.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
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.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
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.\" OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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.\"
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.\" Internet Systems Consortium, Inc.
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.\" 950 Charter Street
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.\" Redwood City, CA 94063
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.\" <info@isc.org>
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.\" http://www.isc.org/
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.\"
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.\" This software has been written for Internet Software Consortium
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.\" by Ted Lemon in cooperation with Vixie Enterprises and Nominum, Inc.
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.\" To learn more about Internet Software Consortium, see
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.\" ``http://www.isc.org/''. To learn more about Vixie Enterprises,
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.\" see ``http://www.vix.com''. To learn more about Nominum, Inc., see
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.\" ``http://www.nominum.com''.
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.\"
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.\" $Id: dhclient.conf.5,v 1.17.84.2 2007/05/23 23:30:32 each Exp $
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.\"
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.TH dhclient.conf 5
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.SH NAME
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dhclient.conf - DHCP client configuration file
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.SH DESCRIPTION
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The dhclient.conf file contains configuration information for
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.IR dhclient,
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the Internet Systems Consortium DHCP Client.
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.PP
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The dhclient.conf file is a free-form ASCII text file. It is parsed by
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the recursive-descent parser built into dhclient. The file may contain
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extra tabs and newlines for formatting purposes. Keywords in the file
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are case-insensitive. Comments may be placed anywhere within the
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file (except within quotes). Comments begin with the # character and
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end at the end of the line.
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.PP
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The dhclient.conf file can be used to configure the behaviour of the
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client in a wide variety of ways: protocol timing, information
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requested from the server, information required of the server,
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defaults to use if the server does not provide certain information,
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values with which to override information provided by the server, or
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values to prepend or append to information provided by the server.
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The configuration file can also be preinitialized with addresses to
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use on networks that don't have DHCP servers.
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.SH PROTOCOL TIMING
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The timing behaviour of the client need not be configured by the user.
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If no timing configuration is provided by the user, a fairly
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reasonable timing behaviour will be used by default - one which
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results in fairly timely updates without placing an inordinate load on
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the server.
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.PP
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The following statements can be used to adjust the timing behaviour of
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the DHCP client if required, however:
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.PP
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.I The
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.B timeout
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.I statement
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.PP
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.B timeout
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.I time
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.B ;
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.PP
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The
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.I timeout
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statement determines the amount of time that must pass between the
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time that the client begins to try to determine its address and the
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time that it decides that it's not going to be able to contact a
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server. By default, this timeout is sixty seconds. After the
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timeout has passed, if there are any static leases defined in the
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configuration file, or any leases remaining in the lease database that
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have not yet expired, the client will loop through these leases
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attempting to validate them, and if it finds one that appears to be
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valid, it will use that lease's address. If there are no valid
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static leases or unexpired leases in the lease database, the client
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will restart the protocol after the defined retry interval.
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.PP
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.I The
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.B retry
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.I statement
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.PP
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\fBretry \fItime\fR\fB;\fR
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.PP
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The
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.I retry
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statement determines the time that must pass after the client has
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determined that there is no DHCP server present before it tries again
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to contact a DHCP server. By default, this is five minutes.
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.PP
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.I The
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.B select-timeout
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.I statement
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.PP
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\fBselect-timeout \fItime\fR\fB;\fR
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.PP
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It is possible (some might say desirable) for there to be more than
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one DHCP server serving any given network. In this case, it is
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possible that a client may be sent more than one offer in response to
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its initial lease discovery message. It may be that one of these
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offers is preferable to the other (e.g., one offer may have the
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address the client previously used, and the other may not).
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.PP
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The
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.I select-timeout
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is the time after the client sends its first lease discovery request
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at which it stops waiting for offers from servers, assuming that it
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has received at least one such offer. If no offers have been
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received by the time the
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.I select-timeout
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has expired, the client will accept the first offer that arrives.
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.PP
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By default, the select-timeout is zero seconds - that is, the client
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will take the first offer it sees.
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.PP
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.I The
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.B reboot
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.I statement
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.PP
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\fBreboot \fItime\fR\fB;\fR
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.PP
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When the client is restarted, it first tries to reacquire the last
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address it had. This is called the INIT-REBOOT state. If it is
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still attached to the same network it was attached to when it last
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ran, this is the quickest way to get started. The
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.I reboot
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statement sets the time that must elapse after the client first tries
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to reacquire its old address before it gives up and tries to discover
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a new address. By default, the reboot timeout is ten seconds.
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.PP
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.I The
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.B backoff-cutoff
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.I statement
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.PP
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\fBbackoff-cutoff \fItime\fR\fB;\fR
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.PP
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The client uses an exponential backoff algorithm with some randomness,
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so that if many clients try to configure themselves at the same time,
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they will not make their requests in lockstep. The
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.I backoff-cutoff
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statement determines the maximum amount of time that the client is
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allowed to back off, the actual value will be evaluated randomly between
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1/2 to 1 1/2 times the \fItime\fR specified. It defaults to two minutes.
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.PP
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.I The
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.B initial-interval
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.I statement
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.PP
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\fBinitial-interval \fItime\fR\fB;\fR
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.PP
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The
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.I initial-interval
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statement sets the amount of time between the first attempt to reach a
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server and the second attempt to reach a server. Each time a message
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is sent, the interval between messages is incremented by twice the
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current interval multiplied by a random number between zero and one.
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If it is greater than the backoff-cutoff amount, it is set to that
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amount. It defaults to ten seconds.
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.SH LEASE REQUIREMENTS AND REQUESTS
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The DHCP protocol allows the client to request that the server send it
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specific information, and not send it other information that it is not
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prepared to accept. The protocol also allows the client to reject
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offers from servers if they don't contain information the client
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needs, or if the information provided is not satisfactory.
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.PP
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There is a variety of data contained in offers that DHCP servers send
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to DHCP clients. The data that can be specifically requested is what
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are called \fIDHCP Options\fR. DHCP Options are defined in
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\fBdhcp-options(5)\fR.
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.PP
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.I The
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.B request
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.I statement
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.PP
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\fBrequest [ \fIoption\fR ] [\fB,\fI ... \fIoption\fR ]\fB;\fR
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.PP
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The request statement causes the client to request that any server
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responding to the client send the client its values for the specified
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options. Only the option names should be specified in the request
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statement - not option parameters. By default, the DHCP server
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requests the subnet-mask, broadcast-address, time-offset, routers,
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domain-name, domain-name-servers, host-name, nis-domain, nis-servers,
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and ntp-servers options.
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.PP
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In some cases, it may be desirable to send no parameter request list
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at all. To do this, simply write the request statement but specify
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no parameters:
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.PP
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.nf
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request;
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.fi
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.PP
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.I The
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.B require
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.I statement
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.PP
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\fBrequire [ \fIoption\fR ] [\fB,\fI ... \fIoption ]\fB;\fR
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.PP
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The require statement lists options that must be sent in order for an
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offer to be accepted. Offers that do not contain all the listed
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options will be ignored.
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.PP
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.I The
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.B send
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.I statement
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.PP
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\fBsend { [ \fIoption declaration\fR ]
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[\fB,\fI ... \fIoption declaration\fR ]\fB}\fR
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.PP
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The send statement causes the client to send the specified options to
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the server with the specified values. These are full option
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declarations as described in \fBdhcp-options(5)\fR. Options that are
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always sent in the DHCP protocol should not be specified here, except
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that the client can specify a \fBrequested-lease-time\fR option other
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than the default requested lease time, which is two hours. The other
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obvious use for this statement is to send information to the server
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that will allow it to differentiate between this client and other
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clients or kinds of clients.
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.SH DYNAMIC DNS
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The client now has some very limited support for doing DNS updates
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when a lease is acquired. This is prototypical, and probably doesn't
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do what you want. It also only works if you happen to have control
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over your DNS server, which isn't very likely.
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.PP
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To make it work, you have to declare a key and zone as in the DHCP
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server (see \fBdhcpd.conf\fR(5) for details). You also need to
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configure the fqdn option on the client, as follows:
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.PP
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.nf
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send fqdn.fqdn "grosse.fugue.com.";
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send fqdn.encoded on;
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send fqdn.server-update off;
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.fi
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.PP
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The \fIfqdn.fqdn\fR option \fBMUST\fR be a fully-qualified domain
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name. You \fBMUST\fR define a zone statement for the zone to be
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updated. The \fIfqdn.encoded\fR option may need to be set to
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\fIon\fR or \fIoff\fR, depending on the DHCP server you are using.
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.PP
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.I The
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.B do-forward-updates
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.I statement
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.PP
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\fBdo-forward-updates [ \fIflag\fR ] \fB;\fR
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.PP
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If you want to do DNS updates in the DHCP client
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script (see \fBdhclient-script(8)\fR) rather than having the
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DHCP client do the update directly (for example, if you want to
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use SIG(0) authentication, which is not supported directly by the
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DHCP client, you can instruct the client not to do the update using
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the \fBdo-forward-updates\fR statement. \fIFlag\fR should be \fBtrue\fR
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if you want the DHCP client to do the update, and \fBfalse\fR if
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you don't want the DHCP client to do the update. By default, the DHCP
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client will do the DNS update.
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.SH OPTION MODIFIERS
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In some cases, a client may receive option data from the server which
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is not really appropriate for that client, or may not receive
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information that it needs, and for which a useful default value
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exists. It may also receive information which is useful, but which
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needs to be supplemented with local information. To handle these
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needs, several option modifiers are available.
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.PP
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.I The
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.B default
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.I statement
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.PP
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\fBdefault [ \fIoption declaration\fR ] \fB;\fR
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.PP
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If for some option the client should use the value supplied by
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the server, but needs to use some default value if no value was supplied
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by the server, these values can be defined in the
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.B default
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statement.
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.PP
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.I The
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.B supersede
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.I statement
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.PP
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\fBsupersede [ \fIoption declaration\fR ] \fB;\fR
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.PP
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If for some option the client should always use a locally-configured
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value or values rather than whatever is supplied by the server, these
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values can be defined in the
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.B supersede
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statement.
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.PP
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.I The
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.B prepend
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.I statement
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.PP
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\fBprepend [ \fIoption declaration\fR ] \fB;\fR
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.PP
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If for some set of options the client should use a value you
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supply, and then use the values supplied by
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the server, if any, these values can be defined in the
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.B prepend
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statement. The
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.B prepend
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statement can only be used for options which
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allow more than one value to be given. This restriction is not
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enforced - if you ignore it, the behaviour will be unpredictable.
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.PP
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.I The
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.B append
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.I statement
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.PP
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\fBappend [ \fIoption declaration\fR ] \fB;\fR
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.PP
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If for some set of options the client should first use the values
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supplied by the server, if any, and then use values you supply, these
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values can be defined in the
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.B append
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statement. The
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.B append
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statement can only be used for options which
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allow more than one value to be given. This restriction is not
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enforced - if you ignore it, the behaviour will be unpredictable.
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.SH LEASE DECLARATIONS
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.PP
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.I The
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.B lease
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.I declaration
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.PP
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\fBlease {\fR \fIlease-declaration\fR [ ... \fIlease-declaration ] \fB}\fR
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.PP
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The DHCP client may decide after some period of time (see \fBPROTOCOL
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TIMING\fR) that it is not going to succeed in contacting a
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server. At that time, it consults its own database of old leases and
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tests each one that has not yet timed out by pinging the listed router
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for that lease to see if that lease could work. It is possible to
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define one or more \fIfixed\fR leases in the client configuration file
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for networks where there is no DHCP or BOOTP service, so that the
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client can still automatically configure its address. This is done
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with the
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.B lease
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statement.
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.PP
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NOTE: the lease statement is also used in the dhclient.leases file in
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order to record leases that have been received from DHCP servers.
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Some of the syntax for leases as described below is only needed in the
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dhclient.leases file. Such syntax is documented here for
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completeness.
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.PP
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A lease statement consists of the lease keyword, followed by a left
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curly brace, followed by one or more lease declaration statements,
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followed by a right curly brace. The following lease declarations
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are possible:
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.PP
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\fBbootp;\fR
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.PP
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The
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.B bootp
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statement is used to indicate that the lease was acquired using the
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BOOTP protocol rather than the DHCP protocol. It is never necessary
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to specify this in the client configuration file. The client uses
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this syntax in its lease database file.
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.PP
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\fBinterface\fR \fB"\fR\fIstring\fR\fB";\fR
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.PP
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The
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.B interface
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lease statement is used to indicate the interface on which the lease
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is valid. If set, this lease will only be tried on a particular
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interface. When the client receives a lease from a server, it always
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records the interface number on which it received that lease.
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If predefined leases are specified in the dhclient.conf file, the
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interface should also be specified, although this is not required.
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.PP
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\fBfixed-address\fR \fIip-address\fR\fB;\fR
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.PP
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The
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.B fixed-address
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statement is used to set the ip address of a particular lease. This
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is required for all lease statements. The IP address must be
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specified as a dotted quad (e.g., 12.34.56.78).
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.PP
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\fBfilename "\fR\fIstring\fR\fB";\fR
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.PP
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The
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.B filename
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statement specifies the name of the boot filename to use. This is
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not used by the standard client configuration script, but is included
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for completeness.
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.PP
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\fBserver-name "\fR\fIstring\fR\fB";\fR
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.PP
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The
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.B server-name
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statement specifies the name of the boot server name to use. This is
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also not used by the standard client configuration script.
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.PP
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\fBoption\fR \fIoption-declaration\fR\fB;\fR
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.PP
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The
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.B option
|
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statement is used to specify the value of an option supplied by the
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server, or, in the case of predefined leases declared in
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dhclient.conf, the value that the user wishes the client configuration
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script to use if the predefined lease is used.
|
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.PP
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\fBscript "\fIscript-name\fB";\fR
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.PP
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|
The
|
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.B script
|
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statement is used to specify the pathname of the dhcp client
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configuration script. This script is used by the dhcp client to set
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each interface's initial configuration prior to requesting an address,
|
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to test the address once it has been offered, and to set the
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interface's final configuration once a lease has been acquired. If
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no lease is acquired, the script is used to test predefined leases, if
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any, and also called once if no valid lease can be identified. For
|
|
more information, see
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.B dhclient-script(8).
|
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.PP
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|
\fBvendor option space "\fIname\fB";\fR
|
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.PP
|
|
The
|
|
.B vendor option space
|
|
statement is used to specify which option space should be used for
|
|
decoding the vendor-encapsulate-options option if one is received.
|
|
The \fIdhcp-vendor-identifier\fR can be used to request a specific
|
|
class of vendor options from the server. See
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.B dhcp-options(5)
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|
for details.
|
|
.PP
|
|
\fBmedium "\fImedia setup\fB";\fR
|
|
.PP
|
|
The
|
|
.B medium
|
|
statement can be used on systems where network interfaces cannot
|
|
automatically determine the type of network to which they are
|
|
connected. The media setup string is a system-dependent parameter
|
|
which is passed to the dhcp client configuration script when
|
|
initializing the interface. On Unix and Unix-like systems, the
|
|
argument is passed on the ifconfig command line when configuring the
|
|
interface.
|
|
.PP
|
|
The dhcp client automatically declares this parameter if it uses a
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media type (see the
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.B media
|
|
statement) when configuring the interface in order to obtain a lease.
|
|
This statement should be used in predefined leases only if the network
|
|
interface requires media type configuration.
|
|
.PP
|
|
\fBrenew\fR \fIdate\fB;\fR
|
|
.PP
|
|
\fBrebind\fR \fIdate\fB;\fR
|
|
.PP
|
|
\fBexpire\fR \fIdate\fB;\fR
|
|
.PP
|
|
The \fBrenew\fR statement defines the time at which the dhcp client
|
|
should begin trying to contact its server to renew a lease that it is
|
|
using. The \fBrebind\fR statement defines the time at which the dhcp
|
|
client should begin to try to contact \fIany\fR dhcp server in order
|
|
to renew its lease. The \fBexpire\fR statement defines the time at
|
|
which the dhcp client must stop using a lease if it has not been able
|
|
to contact a server in order to renew it.
|
|
.PP
|
|
These declarations are automatically set in leases acquired by the
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|
DHCP client, but must also be configured in predefined leases - a
|
|
predefined lease whose expiry time has passed will not be used by the
|
|
DHCP client.
|
|
.PP
|
|
Dates are specified as follows:
|
|
.PP
|
|
\fI<weekday> <year>\fB/\fI<month>\fB/\fI<day>
|
|
<hour>\fB:\fI<minute>\fB:\fI<second>\fR
|
|
.PP
|
|
The weekday is present to make it easy for a human to tell when a
|
|
lease expires - it's specified as a number from zero to six, with zero
|
|
being Sunday. When declaring a predefined lease, it can always be
|
|
specified as zero. The year is specified with the century, so it
|
|
should generally be four digits except for really long leases. The
|
|
month is specified as a number starting with 1 for January. The day
|
|
of the month is likewise specified starting with 1. The hour is a
|
|
number between 0 and 23, the minute a number between 0 and 59, and the
|
|
second also a number between 0 and 59.
|
|
.SH ALIAS DECLARATIONS
|
|
\fBalias { \fI declarations ... \fB}\fR
|
|
.PP
|
|
Some DHCP clients running TCP/IP roaming protocols may require that in
|
|
addition to the lease they may acquire via DHCP, their interface also
|
|
be configured with a predefined IP alias so that they can have a
|
|
permanent IP address even while roaming. The Internet Systems
|
|
Consortium DHCP client doesn't support roaming with fixed addresses
|
|
directly, but in order to facilitate such experimentation, the dhcp
|
|
client can be set up to configure an IP alias using the
|
|
.B alias
|
|
declaration.
|
|
.PP
|
|
The alias declaration resembles a lease declaration, except that
|
|
options other than the subnet-mask option are ignored by the standard
|
|
client configuration script, and expiry times are ignored. A typical
|
|
alias declaration includes an interface declaration, a fixed-address
|
|
declaration for the IP alias address, and a subnet-mask option
|
|
declaration. A medium statement should never be included in an alias
|
|
declaration.
|
|
.SH OTHER DECLARATIONS
|
|
\fBreject \fIcidr-ip-address\fR [\fB,\fR \fI...\fB \fIcidr-ip-address\fR ] \fB;\fR
|
|
.PP
|
|
The
|
|
.B reject
|
|
statement causes the DHCP client to reject offers from
|
|
servers whose server identifier matches any of the specified hosts or
|
|
subnets. 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.
|
|
.PP
|
|
The \fIcidr-ip-address\fR configuration type is of the
|
|
form \fIip-address\fR[\fB/\fIprefixlen\fR], where \fIip-address\fR is a
|
|
dotted quad IP address, and \fRprefixlen\fR is the CIDR prefix length of
|
|
the subnet, counting the number of significant bits in the netmask starting
|
|
from the leftmost end. Example configuration syntax:
|
|
.PP
|
|
\fIreject\fR 192.168.0.0\fB/\fR16\fB,\fR 10.0.0.5\fB;\fR
|
|
.PP
|
|
The above example would cause offers from any server identifier in the
|
|
entire RFC 1918 "Class C" network 192.168.0.0/16, or the specific
|
|
single address 10.0.0.5, to be rejected.
|
|
.PP
|
|
\fBinterface "\fIname\fB" { \fIdeclarations ... \fB }
|
|
.PP
|
|
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.
|
|
.PP
|
|
.B Note well:
|
|
ISC dhclient only maintains one list of interfaces, which is either
|
|
determined at startup from command line arguments, or otherwise is
|
|
autodetected. If you supplied the list of interfaces on the command
|
|
line, this configuration clause will add the named interface to the
|
|
list in such a way that will cause it to be configured by DHCP. Which
|
|
may not be the result you had intended. This is an undesirable side
|
|
effect that will be addressed in a future release.
|
|
.PP
|
|
\fBpseudo "\fIname\fR" "\fIreal-name\fB" { \fIdeclarations ... \fB }
|
|
.PP
|
|
Under some circumstances it can be useful to declare a pseudo-interface
|
|
and have the DHCP client acquire a configuration for that interface.
|
|
Each interface that the DHCP client is supporting normally has a DHCP
|
|
client state machine running on it to acquire and maintain its lease.
|
|
A pseudo-interface is just another state machine running on the
|
|
interface named \fIreal-name\fR, with its own lease and its own
|
|
state. If you use this feature, you must provide a client identifier
|
|
for both the pseudo-interface and the actual interface, and the two
|
|
identifiers must be different. You must also provide a separate
|
|
client script for the pseudo-interface to do what you want with the IP
|
|
address. For example:
|
|
.PP
|
|
.nf
|
|
interface "ep0" {
|
|
send dhcp-client-identifier "my-client-ep0";
|
|
}
|
|
pseudo "secondary" "ep0" {
|
|
send dhcp-client-identifier "my-client-ep0-secondary";
|
|
script "/etc/dhclient-secondary";
|
|
}
|
|
.fi
|
|
.PP
|
|
The client script for the pseudo-interface should not configure the
|
|
interface up or down - essentially, all it needs to handle are the
|
|
states where a lease has been acquired or renewed, and the states
|
|
where a lease has expired. See \fBdhclient-script(8)\fR for more
|
|
information.
|
|
.PP
|
|
\fBmedia "\fImedia setup\fB"\fI [ \fB, "\fImedia setup\fB", \fI... ]\fB;\fR
|
|
.PP
|
|
The
|
|
.B media
|
|
statement defines one or more media configuration parameters which may
|
|
be tried while attempting to acquire an IP address. The dhcp client
|
|
will cycle through each media setup string on the list, configuring
|
|
the interface using that setup and attempting to boot, and then trying
|
|
the next one. This can be used for network interfaces which aren't
|
|
capable of sensing the media type unaided - whichever media type
|
|
succeeds in getting a request to the server and hearing the reply is
|
|
probably right (no guarantees).
|
|
.PP
|
|
The media setup is only used for the initial phase of address
|
|
acquisition (the DHCPDISCOVER and DHCPOFFER packets). Once an
|
|
address has been acquired, the dhcp client will record it in its lease
|
|
database and will record the media type used to acquire the address.
|
|
Whenever the client tries to renew the lease, it will use that same
|
|
media type. The lease must expire before the client will go back to
|
|
cycling through media types.
|
|
.PP
|
|
\fBbootp-broadcast-always;\fR
|
|
.PP
|
|
The
|
|
.B bootp-broadcast-always
|
|
statement instructs dhclient to always set the bootp broadcast flag in
|
|
request packets, so that servers will always broadcast replies.
|
|
This is equivalent to supplying the dhclient -B argument, and has
|
|
the same effect as specifying 'always-broadcast' in the server's dhcpd.conf.
|
|
This option is provided as an extension to enable dhclient to work
|
|
on IBM s390 Linux guests.
|
|
.PP
|
|
.SH SAMPLE
|
|
The following configuration file is used on a laptop running NetBSD
|
|
1.3. The laptop has an IP alias of 192.5.5.213, and has one
|
|
interface, ep0 (a 3com 3C589C). Booting intervals have been
|
|
shortened somewhat from the default, because the client is known to
|
|
spend most of its time on networks with little DHCP activity. The
|
|
laptop does roam to multiple networks.
|
|
|
|
.nf
|
|
|
|
timeout 60;
|
|
retry 60;
|
|
reboot 10;
|
|
select-timeout 5;
|
|
initial-interval 2;
|
|
reject 192.33.137.209;
|
|
|
|
interface "ep0" {
|
|
send host-name "andare.fugue.com";
|
|
send dhcp-client-identifier 1:0:a0:24:ab:fb:9c;
|
|
send dhcp-lease-time 3600;
|
|
supersede domain-name "fugue.com rc.vix.com home.vix.com";
|
|
prepend domain-name-servers 127.0.0.1;
|
|
request subnet-mask, broadcast-address, time-offset, routers,
|
|
domain-name, domain-name-servers, host-name;
|
|
require subnet-mask, domain-name-servers;
|
|
script "CLIENTBINDIR/dhclient-script";
|
|
media "media 10baseT/UTP", "media 10base2/BNC";
|
|
}
|
|
|
|
alias {
|
|
interface "ep0";
|
|
fixed-address 192.5.5.213;
|
|
option subnet-mask 255.255.255.255;
|
|
}
|
|
.fi
|
|
This is a very complicated dhclient.conf file - in general, yours
|
|
should be much simpler. In many cases, it's sufficient to just
|
|
create an empty dhclient.conf file - the defaults are usually fine.
|
|
.SH SEE ALSO
|
|
dhcp-options(5), dhcp-eval(5), dhclient.leases(5), dhcpd(8), dhcpd.conf(5),
|
|
RFC2132, RFC2131.
|
|
.SH AUTHOR
|
|
.B dhclient(8)
|
|
was written by Ted Lemon
|
|
under a contract with Vixie Labs. Funding
|
|
for this project was provided by Internet Systems Consortium.
|
|
Information about Internet Systems Consortium can be found at
|
|
.B http://www.isc.org.
|