Ubuntu Manpage: dhcpcd-run-hooks — DHCP client configuration script

name
description
files
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authors
bugs
security considerations

Provided by: dhcpcd5_6.0.5-2build0.14.04.1_amd64

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.

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.

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.

IPV4LL dhcpcd failed to contact any DHCP servers but did obtain an IPV4LL address.

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.

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

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.

STOP | STOP6 dhcpcd stopped running on the interface.

DEPARTED The interface has been removed.

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.

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

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

AUTHORS

     Roy Marples <roy@marples.name>

BUGS

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

SECURITY CONSIDERATIONS

     Little validation of DHCP options is done in dhcpcd itself.  Instead, it is up to the hooks to handle any
     validation needed.  To this end, some helper functions are provided, such as valid_domainname as used by
     the 20-resolv.conf hook to ensure that the hostname is not set to an invalid value.  valid_path is also
     provided, but is currently unused by a stock hook script.