diff options
Diffstat (limited to 'contrib/isc-dhcp/client/dhclient-script.8')
| -rw-r--r-- | contrib/isc-dhcp/client/dhclient-script.8 | 60 |
1 files changed, 30 insertions, 30 deletions
diff --git a/contrib/isc-dhcp/client/dhclient-script.8 b/contrib/isc-dhcp/client/dhclient-script.8 index 82212db6cf6d..02b22527f4bd 100644 --- a/contrib/isc-dhcp/client/dhclient-script.8 +++ b/contrib/isc-dhcp/client/dhclient-script.8 @@ -1,8 +1,6 @@ .\" dhclient-script.8 .\" -.\" Copyright (c) 1997 The Internet Software Consortium. -.\" All rights reserved. -.\" +.\" Copyright (c) 1996-2001 Internet Software Consortium. .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: @@ -31,10 +29,11 @@ .\" 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''. +.\" by Ted Lemon in cooperation with Vixie Enterprises and Nominum, Inc. +.\" To learn more about the Internet Software Consortium, see +.\" ``http://www.isc.org/''. To learn more about Vixie Enterprises, +.\" see ``http://www.vix.com''. To learn more about Nominum, Inc., see +.\" ``http://www.nominum.com''. .TH dhclient-script 8 .SH NAME dhclient-script - DHCP client network configuration script @@ -61,7 +60,7 @@ to a particular computer should be done in the .B ETCDIR/dhclient.conf file. If you find that you can't make such a customization without customizing -.B dhclient-script +.B ETCDIR/dhclient.conf or using the enter and exit hooks, please submit a bug report. .SH HOOKS When it starts, the client script first defines a shell function, @@ -80,23 +79,29 @@ is available to this script, which may modify the environment if needed to change the behaviour of the script. If an error occurs during the execution of the script, it can set the exit_status variable to a nonzero value, and -.B ETCDIR/dhclient-script +.B CLIENTBINDIR/dhclient-script will exit with that error code immediately after the client script exits. .PP After all processing has completed, -.B ETCDIR/dhclient-script +.B CLIENTBINDIR/dhclient-script checks for the presence of an executable .B ETCDIR/dhclient-exit-hooks -script, which if present is invoked using the '.' command. The exit status -is passed in the exit_status shell variable, and will always be zero if the -script succeeded at the task for which it was invoked. +script, which if present is invoked using the '.' command. The exit +status of dhclient-script will be passed to dhclient-exit-hooks in the +exit_status shell variable, and will always be zero if the script +succeeded at the task for which it was invoked. The rest of the +environment as described previously for dhclient-enter-hooks is also +present. The +.B ETCDIR/dhclient-exit-hooks +script can modify the valid of exit_status to change the exit status +of dhclient-script. .SH OPERATION When dhclient needs to invoke the client configuration script, it -writes a shell script into /tmp which defines a variety of variables. +defines a set of variables in the environment, and then invokes +.B CLIENTBINDIR/dhclient-script. 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. +MEDIUM, PREINIT, BOUND, RENEW, REBIND, REBOOT, EXPIRE, FAIL and TIMEOUT. .PP .SH MEDIUM The DHCP client is requesting that an interface's media type @@ -115,18 +120,6 @@ and the media type in $medium. 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 ARPSEND 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 @@ -137,6 +130,13 @@ 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 +Before actually configuring the address, dhclient-script should +somehow ARP for it and exit with a nonzero status if it receives a +reply. In this case, the client will send a DHCPDECLINE message to +the server and acquire a different address. This may also be done in +the RENEW, REBIND, or REBOOT states, but is not required, and indeed +may not be desirable. +.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 @@ -216,10 +216,10 @@ dhclient.leases(5). .SH AUTHOR .B dhclient-script(8) has been written for the Internet Software Consortium -by Ted Lemon <mellon@fugue.com> in cooperation with Vixie +by Ted Lemon in cooperation with Vixie Enterprises. To learn more about the Internet Software Consortium, see -.B http://www.vix.com/isc. +.B http://www.isc.org. To learn more about Vixie Enterprises, see .B http://www.vix.com. |