NAME

     dhcpcd-run-hooks — DHCP client configuration script

DESCRIPTION

     dhcpcd-run-hooks is used by dhcpcd(8) to run any system and user defined hook scripts.  System hook scripts
     are found in /lib/dhcpcd/dhcpcd-hooks and the user defined hooks are /etc/dhcpcd.enter-hook.  and
     /etc/dhcpcd.exit-hook.  The default install supplies hook scripts for configuring /etc/resolv.conf and the
     hostname.  Your distribution may have included other hook scripts to say configure ntp or ypbind.  A test
     hook is also supplied that simply echos the dhcp variables to the console from DISCOVER message.

     The hooks scripts are loaded into the current shell rather than executed in their own process.  This allows
     each hook script, such as /etc/dhcpcd.enter-hook to customise environment variables or provide alternative
     functions to hooks further down the chain.  As such, using the shell builtins exit, exec or similar will
     cause dhcpcd-run-hooks to exit at that point.

     Each time dhcpcd-run-hooks is invoked, $interface is set to the interface that dhcpcd is run on and $reason
     is to the reason why dhcpcd-run-hooks was invoked.  DHCP information to be configured is held in variables
     starting with the word new_ and old DHCP information to be removed is held in variables starting with the
     word old_.  dhcpcd can display the full list of variables it knows how about by using the -V, --variables
     argument.

     Here's a list of reasons why dhcpcd-run-hooks could be invoked:

     PREINIT           dhcpcd is starting up and any pre-initialisation should be done.

     CARRIER           dhcpcd has detected the carrier is up.  This is generally just a notification and no
                       action need be taken.

     NOCARRIER         dhcpcd lost the carrier.  The cable may have been unplugged or association to the
                       wireless point lost.

     INFORM | INFORM6  dhcpcd informed a DHCP server about it's address and obtained other configuration
                       details.

     BOUND | BOUND6    dhcpcd obtained a new lease from a DHCP server.

     RENEW | RENEW6    dhcpcd renewed it's lease.

     REBIND | REBIND6  dhcpcd has rebound to a new DHCP server.

     REBOOT | REBOOT6  dhcpcd successfully requested a lease from a DHCP server.

     DELEGATED6        dhcpcd assigned a delegated prefix to the interface.

     IPV4LL            dhcpcd obtained an IPV4LL address, or one was removed.

     STATIC            dhcpcd has been configured with a static configuration which has not been obtained from a
                       DHCP server.

     3RDPARTY          dhcpcd is monitoring the interface for a 3rd party to give it an IP address.

     TIMEOUT           dhcpcd failed to contact any DHCP servers but was able to use an old lease.

     EXPIRE | EXPIRE6  dhcpcd's lease or state expired and it failed to obtain a new one.

     NAK               dhcpcd received a NAK from the DHCP server.  This should be treated as EXPIRE.

     RECONFIGURE       dhcpcd has been instructed to reconfigure an interface.

     ROUTERADVERT      dhcpcd has received an IPv6 Router Advertisement, or one has expired.

     STOP | STOP6      dhcpcd stopped running on the interface.

     STOPPED           dhcpcd has stopped entirely.

     DEPARTED          The interface has been removed.

     FAIL              dhcpcd failed to operate on the interface.  This normally happens when dhcpcd does not
                       support the raw interface, which means it cannot work as a DHCP or ZeroConf client.
                       Static configuration and DHCP INFORM is still allowed.

     DUMP              dhcpcd has been asked to dump the last lease for the interface.

     TEST              dhcpcd received an OFFER from a DHCP server but will not configure the interface.  This
                       is primarily used to test the variables are filled correctly for the script to process
                       them.

ENVIRONMENT

     dhcpcd will clear the environment variables aside from $PATH and $RC_SVCNAME.  The following variables will
     then be set, along with any protocol supplied ones.

     $interface                   the name of the interface.

     $protocol                    the protocol that triggered the event.

     $reason                      as described above.

     $pid                         the pid of dhcpcd.

     $ifcarrier                   the link status of $interface: unknown, up or down.

     $ifmetric                    $interface preference, lower is better.

     $ifwireless                  1 if $interface is wireless, otherwise 0.

     $ifflags                     $interface flags.

     $ifmtu                       $interface MTU.

     $ifssid                      the name of the SSID the interface is connected to.

     $interface_order             A list of interfaces, in order of preference.

     $if_up                       true if the interface is up, otherwise false.

     $if_down                     true if the interface is down, otherwise false.

     $af_waiting                  Address family waiting for, as defined in dhcpcd.conf(5).

     $profile                     the name of the profile selected from dhcpcd.conf(5).

     $new_delegated_dhcp6_prefix  space separated list of delegated prefixes.

FILES

     When dhcpcd-run-hooks runs, it loads /etc/dhcpcd.enter-hook and any scripts found in
     /lib/dhcpcd/dhcpcd-hooks in a lexical order and then finally /etc/dhcpcd.exit-hook

SEE ALSO

     dhcpcd(8)

AUTHORS

     Roy Marples <roy@marples.name>

BUGS

     Please report them to http://roy.marples.name/projects/dhcpcd

SECURITY CONSIDERATIONS

     dhcpcd will validate the content of each option against its encoding.  For string, ascii, raw or binhex
     encoding it's up to the user to validate it for the intended purpose.

     When used in a shell script, each variable must be quoted correctly.