Updated: 2021/Apr/14

DHCPCD-RUN-HOOKS(8)         System Manager's Manual        DHCPCD-RUN-HOOKS(8)

     dhcpcd-run-hooks - DHCP client configuration script

     dhcpcd-run-hooks is used by dhcpcd(8) to run any system and user defined
     hook scripts.  System hook scripts are found in /libexec/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 q 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

     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

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

                       dhcpcd lost the carrier but the interface configuration
                       is persisted.  The OS has to support wireless roaming
                       or IP Persistance for this to happen.

     INFORM | INFORM6  dhcpcd informed a DHCP server about its 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

     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.

     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.

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

     $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

     $if_up                       true if the interface is up, otherwise
                                  false.  This is more than IFF_UP and may not
                                  be equal.

     $if_down                     true if the interface is down, otherwise
                                  false.  This is more than IFF_UP and may not
                                  be equal.

     $af_waiting                  Address family waiting for, as defined in

     $profile                     the name of the profile selected from

     $new_delegated_dhcp6_prefix  space separated list of delegated prefixes.

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


     Roy Marples <roy@marples.name>

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

     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.

NetBSD 9.99                    December 27, 2020                   NetBSD 9.99