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Diffstat (limited to 'contrib/isc-dhcp/client/dhclient-script.8')
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diff --git a/contrib/isc-dhcp/client/dhclient-script.8 b/contrib/isc-dhcp/client/dhclient-script.8 deleted file mode 100644 index 1a1d78b9d5b4d..0000000000000 --- a/contrib/isc-dhcp/client/dhclient-script.8 +++ /dev/null @@ -1,190 +0,0 @@ -.\" dhclient-script.8 -.\" -.\" Copyright (c) 1997 The Internet Software Consortium. -.\" All rights reserved. -.\" -.\" Redistribution and use in source and binary forms, with or without -.\" modification, are permitted provided that the following conditions -.\" are met: -.\" -.\" 1. Redistributions of source code must retain the above copyright -.\" notice, this list of conditions and the following disclaimer. -.\" 2. Redistributions in binary form must reproduce the above copyright -.\" notice, this list of conditions and the following disclaimer in the -.\" documentation and/or other materials provided with the distribution. -.\" 3. Neither the name of The Internet Software Consortium nor the names -.\" of its contributors may be used to endorse or promote products derived -.\" from this software without specific prior written permission. -.\" -.\" THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND -.\" CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, -.\" INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF -.\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE -.\" DISCLAIMED. IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR -.\" CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, -.\" SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT -.\" LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF -.\" USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND -.\" ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, -.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT -.\" OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF -.\" SUCH DAMAGE. -.\" -.\" This software has been written for the Internet Software Consortium -.\" by Ted Lemon <mellon@fugue.com> in cooperation with Vixie -.\" Enterprises. To learn more about the Internet Software Consortium, -.\" see ``http://www.isc.org/isc''. To learn more about Vixie -.\" Enterprises, see ``http://www.vix.com''. -.TH dhclient 8 -.SH NAME -dhclient-script - DHCP client network configuration script -.SH DESCRIPTION -The DHCP client network configuration script is invoked from time to -time by \fBdhclient(8)\fR. This script is used by the dhcp client to -set each interface's initial configuration prior to requesting an -address, to test the address once it has been offered, and to set the -interface's final configuration once a lease has been acquired. If no -lease is acquired, the script is used to test predefined leases, if -any, and also called once if no valid lease can be identified. -.PP -This script is not meant to be customized by the end user. However, -the script may not work on particular versions of particular operating -systems (indeed, no standard script exists for some operating -systems), so a pioneering user may well need to create a new script or -modify an existing one. In general, customizations specific to a -particular computer should be done in the -.B /etc/dhclient.conf -script. If you find that you can't make such a customization without -customizing dhclient.conf, please submit a bug report. -.SH OPERATION -When dhclient needs to invoke the client configuration script, it -writes a shell script into /tmp which defines a variety of variables. -In all cases, $reason is set to the name of the reason why the script -has been invoked. The following reasons are currently defined: -MEDIUM, PREINIT, ARPCHECK, ARPSEND, BOUND, RENEW, REBIND, REBOOT, -EXPIRE, FAIL and TIMEOUT. -.PP -.SH MEDIUM -The DHCP client is requesting that an interface's media type -be set. The interface name is passed in $interface, and the media -type is passed in $medium. -.SH PREINIT -The DHCP client is requesting that an interface be configured as -required in order to send packets prior to receiving an actual -address. For clients which use the BSD socket library, this means -configuring the interface with an IP address of 0.0.0.0 and a -broadcast address of 255.255.255.255. For other clients, it may be -possible to simply configure the interface up without actually giving -it an IP address at all. The interface name is passed in $interface, -and the media type in $medium. -.PP -If an IP alias has been declared in dhclient.conf, its address will be -passed in $alias_ip_address, and that ip alias should be deleted from -the interface, along with any routes to it. -.SH ARPSEND -The DHCP client is requesting that an address that has been offered to -it be checked to see if somebody else is using it, by sending an ARP -request for that address. It's not clear how to implement this, so -no examples exist yet. The IP address to check is passed in -$new_ip_address, and the interface name is passed in $interface. -.SH ARPCHECK -The DHCP client wants to know if a response to the ARP request send -using ARPCHECK has been received. If one has, the script should exit -with a nonzero status, indicating that the offered address has already -been requested and should be declined. $new_ip_address and -$interface are set as with ARPSEND. -.SH BOUND -The DHCP client has done an initial binding to a new address. The -new ip address is passed in $new_ip_address, and the interface name is -passed in $interface. The media type is passed in $medium. Any -options acquired from the server are passed using the option name -described in \fBdhcp-options\fR, except that dashes ('-') are replaced -by underscores ('_') in order to make valid shell variables, and the -variable names start with new_. So for example, the new subnet mask -would be passed in $new_subnet_mask. -.PP -When a binding has been completed, a lot of network parameters are -likely to need to be set up. A new /etc/resolv.conf needs to be -created, using the values of $new_domain_name and -$new_domain_name_servers (which may list more than one server, -seperated by spaces). A default route should be set using -$new_routers, and static routes may need to be set up using -$new_static_routes. -.PP -If an IP alias has been declared, it must be set up here. The alias -IP address will be written as $alias_ip_address, and other DHCP -options that are set for the alias (e.g., subnet mask) will be passed -in variables named as described previously except starting with -$alias_ instead of $new_. Care should be taken that the alias IP -address not be used if it is identical to the bound IP address -($new_ip_address), since the other alias parameters may be incorrect -in this case. -.SH RENEW -When a binding has been renewed, the script is called as in BOUND, -except that in addition to all the variables starting with $new_, -there is another set of variables starting with $old_. Persistent -settings that may have changed need to be deleted - for example, if a -local route to the bound address is being configured, the old local -route should be deleted. If the default route has changed, the old default -route should be deleted. If the static routes have changed, the old -ones should be deleted. Otherwise, processing can be done as with -BOUND. -.SH REBIND -The DHCP client has rebound to a new DHCP server. This can be handled -as with RENEW, except that if the IP address has changed, the ARP -table should be cleared. -.SH REBOOT -The DHCP client has successfully reacquired its old address after a -reboot. This can be processed as with BOUND. -.SH EXPIRE -The DHCP client has failed to renew its lease or acquire a new one, -and the lease has expired. The IP address must be relinquished, and -all related parameters should be deleted, as in RENEW and REBIND. -.SH FAIL -The DHCP client has been unable to contact any DHCP servers, and any -leases that have been tested have not proved to be valid. The -parameters from the last lease tested should be deconfigured. This -can be handled in the same way as EXPIRE. -.SH TIMEOUT -The DHCP client has been unable to contact any DHCP servers. -However, an old lease has been identified, and its parameters have -been passed in as with BOUND. The client configuration script should -test these parameters and, if it has reason to believe they are valid, -should exit with a value of zero. If not, it should exit with a -nonzero value. -.PP -The usual way to test a lease is to set up the network as with REBIND -(since this may be called to test more than one lease) and then ping -the first router defined in $routers. If a response is received, the -lease must be valid for the network to which the interface is -currently connected. It would be more complete to try to ping all of -the routers listed in $new_routers, as well as those listed in -$new_static_routes, but current scripts do not do this. -.SH FILES -Each operating system should generally have its own script file, -although the script files for similar operating systems may be similar -or even identical. The script files included in the Internet -Software Consortium DHCP distribution appear in the distribution tree -under client/scripts, and bear the names of the operating systems on -which they are intended to work. -.SH BUGS -If more than one interface is being used, there's no obvious way to -avoid clashes between server-supplied configuration parameters - for -example, the stock dhclient-script rewrites /etc/resolv.conf. If -more than one interface is being configured, /etc/resolv.conf will be -repeatedly initialized to the values provided by one server, and then -the other. Assuming the information provided by both servers is -valid, this shouldn't cause any real problems, but it could be -confusing. -.SH SEE ALSO -dhclient.conf(5), dhclient.leases(5), dhclient(8) -.SH AUTHOR -.B dhclient-script(8) -has been written for the Internet Software Consortium -by Ted Lemon <mellon@fugue.com> in cooperation with Vixie -Enterprises. To learn more about the Internet Software Consortium, -see -.B http://www.vix.com/isc. -To learn more about Vixie -Enterprises, see -.B http://www.vix.com. |