--- dhcp-3.0.5/client/dhclient-script.8.manpages 2005-09-28 15:17:08.000000000 -0400 +++ dhcp-3.0.5/client/dhclient-script.8 2007-04-26 14:52:13.000000000 -0400 @@ -47,7 +47,7 @@ exit hooks provided (see HOOKS for details). These hooks will allow the user to override the default behaviour of the client in creating a .B /etc/resolv.conf -file. +file, and to handle DHCP options not handled by default. .PP No standard client script exists for some operating systems, even though the actual client may work, so a pioneering user may well need to create @@ -91,6 +91,27 @@ .B ETCDIR/dhclient-exit-hooks script can modify the valid of exit_status to change the exit status of dhclient-script. +.PP +Immediately after dhclient brings an interface UP with a new IP address, +subnet mask, and routes, in the REBOOT/BOUND states, it will check for the +existence of an executable +.B ETCDIR/dhclient-up-hooks +script, and source it if found. This script can handle DHCP options in +the environment that are not handled by default. A per-interface +.B ETCDIR/dhclient-${IF}-up-hooks +script will override the generic script and be sourced when interface +$IF has been brought up. +.PP +Immediately before dhclient brings an interface DOWN, removing its IP +address, subnet mask, and routes, in the STOP/RELEASE states, it will +check for the existence of an executable +.B ETCDIR/dhclient-down-hooks +script, and source it if found. This script can handle DHCP options in +the environment that are not handled by default. A per-interface +.B ETCDIR/dhclient-${IF}-down-hooks +script will override the generic script and be sourced when interface +$IF is about to be brought down. + .SH OPERATION When dhclient needs to invoke the client configuration script, it defines a set of variables in the environment, and then invokes --- dhcp-3.0.5/client/dhclient.conf.5.manpages 2005-06-16 15:40:13.000000000 -0400 +++ dhcp-3.0.5/client/dhclient.conf.5 2007-04-26 14:51:02.000000000 -0400 @@ -185,7 +185,8 @@ options. Only the option names should be specified in the request statement - not option parameters. By default, the DHCP server requests the subnet-mask, broadcast-address, time-offset, routers, -domain-name, domain-name-servers and host-name options. +domain-name, domain-name-servers, host-name, nis-domain, nis-servers, +and ntp-servers options. .PP In some cases, it may be desirable to send no parameter request list at all. To do this, simply write the request statement but specify @@ -581,6 +582,18 @@ 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 a Red Hat extension to enable dhclient to work +on IBM zSeries z/OS 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 --- dhcp-3.0.5/client/dhclient.8.manpages 2007-04-26 14:51:02.000000000 -0400 +++ dhcp-3.0.5/client/dhclient.8 2007-04-26 14:51:02.000000000 -0400 @@ -85,6 +85,28 @@ .B -x ] [ +.B -I +.I dhcp-client-identifier +] +[ +.B -H +.I host-name +.R | +.B -F fqdn.fqdn +] +[ +.B -V +.I vendor-class-identifier +] +[ +.B -R +.I request option list +] +[ +.B -T +.I timeout +] +[ .I if0 [ .I ...ifN @@ -273,6 +295,107 @@ -s dhclient-script environment, which would allow applications running in that environment to handle options they do not know about in advance - this is a Red Hat extension to support dhcdbd and NetworkManager. +.PP +The -I argument allows you to specify the dhcp-client-identifier string, , +to be sent to the dhcp server on the command line. It is equivalent to the +top level dhclient.conf statement: +.br + \fBsend dhcp-client-identifier "";\fR +.br +The -I command line option will override any top level dhclient.conf + 'send dhcp-client-identifier' statement, but more specific per-interface + 'interface "X" { send dhcp-client-identifier...; }' statements in dhclient.conf +will override the -I command line option for interface "X". +This option is provided as a Red Hat extension to enable dhclient to work +on IBM zSeries z/OS Linux guests. +.PP +The -B option instructs dhclient to set the bootp broadcast flag in request +packets, so that servers will always broadcast replies. This is equivalent +to specifying the 'bootp-broadcast-always' option in dhclient.conf, and has +the same effect as specifying 'always-broadcast' in the server's dhcpd.conf. +This option is provided as a Red Hat extension to enable dhclient to work +on IBM zSeries z/OS Linux guests. +.PP +The -H option allows you to specify the DHCP host-name option +to send to the server on the dhclient command line. It is equivalent to the +top level dhclient.conf statement: +.br +\f send host-name "";\fR +.br +The -H option will override any top level dhclient.conf + 'send host-name' statement, but more specific per-interface + 'interface "X" { send host-name...;' statements in dhclient.conf +will override the -H command line option for interface "X". +The host-name option only specifies the client's host name prefix, to which +the server will append the 'ddns-domainname' or 'domain-name' options, if any, +to derive the fully qualified domain name of the client host. +The -H option cannot be used with the -F option. +Only one -H option may be specified. +The -H option is provided as a Red Hat extension to simplify +configuration of clients of DHCP servers that require the host-name option +to be sent (eg. some modern cable modems), and for dynamic DNS updates (DDNS). +.PP +The -F option allows you to specify the DHCP fqdn.fqdn option +to send to the server on the dhclient command line. It is equivalent to the +top level dhclient.conf statement: +.br +\f send fqdn.fqdn "";\fR +.br +The -F option will override any top level dhclient.conf + 'send fqdn.fqdn' statement, but more specific per-interface + 'interface "X" { send fqdn.fqdn...;' statements in dhclient.conf +will override the -F command line option for interface "X". +This option cannot be used with the -H option. +The DHCP fqdn.fqdn option must specify the complete domain name of the client +host, which the server may use for dynamic DNS updates. +Only one -F option may be specified. +The -F option is provided as a Red Hat extension to simplify +configuration of DDNS. +.PP +The -T option allows you to specify the time after which +the dhclient will decide that no DHCP servers can be contacted when +no responses have been received. It is equivalent to the +.br +\f timeout ;\fR +.br +dhclient.conf statement, and will override any such statements in dhclient.conf. +.br +This option is provided as a Red Hat extension. +.PP +The -V option allows you to specify the DHCP +vendor-class-identifier option to send to the server on the dhclient command line. +It is equivalent to the top level dhclient.conf statement: +.br +\f send vendor-class-identifier "";\fR +.br +The -V option will override any top level dhclient.conf + 'send vendor-class-identifier' statement, but more specific per-interface + 'interface "X" { send vendor-class-identifier...;' statements in dhclient.conf +will override the -V command line option for interface "X". +The -V option is provided as a Red Hat extension to simplify +configuration of clients of DHCP servers that require the vendor-class-identifier option +to be sent. +.PP +The -R option allows you to specify the list of options the +client is to request from the server on the dhclient command line. +The option list must be a single string, consisting of option names separated +by at least one comma and optional space characters. The default option list +is : +.br + subnet-mask, broadcast-address, time-offset, routers, +.br + domain-name, domain-name-servers, host-name, nis-domain, +.br + nis-servers, ntp-servers +.br +You can specify a different list of options to request with the -R