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				.Dd October 9, 2019
				.Dt DHCPCD 8
				.Os
				.Sh NAME
				.Nm dhcpcd
				.Nd a DHCP client
				.Sh SYNOPSIS
				.Nm
				.Op Fl 146ABbDdEGgHJKLMNPpqTV
				.Op Fl C , Fl Fl nohook Ar hook
				.Op Fl c , Fl Fl script Ar script
				.Op Fl e , Fl Fl env Ar value
				.Op Fl F , Fl Fl fqdn Ar FQDN
				.Op Fl f , Fl Fl config Ar file
				.Op Fl h , Fl Fl hostname Ar hostname
				.Op Fl I , Fl Fl clientid Ar clientid
				.Op Fl i , Fl Fl vendorclassid Ar vendorclassid
				.Op Fl j , Fl Fl logfile Ar logfile
				.Op Fl l , Fl Fl leasetime Ar seconds
				.Op Fl m , Fl Fl metric Ar metric
				.Op Fl O , Fl Fl nooption Ar option
				.Op Fl o , Fl Fl option Ar option
				.Op Fl Q , Fl Fl require Ar option
				.Op Fl r , Fl Fl request Ar address
				.Op Fl S , Fl Fl static Ar value
				.Op Fl s , Fl Fl inform Ar address Ns Op Ar /cidr Ns Op Ar /broadcast_address
				.Op Fl Fl inform6
				.Op Fl t , Fl Fl timeout Ar seconds
				.Op Fl u , Fl Fl userclass Ar class
				.Op Fl v , Fl Fl vendor Ar code , Ar value
				.Op Fl W , Fl Fl whitelist Ar address Ns Op Ar /cidr
				.Op Fl w
				.Op Fl Fl waitip Ns = Ns Op 4 \| 6
				.Op Fl y , Fl Fl reboot Ar seconds
				.Op Fl X , Fl Fl blacklist Ar address Ns Op Ar /cidr
				.Op Fl Z , Fl Fl denyinterfaces Ar pattern
				.Op Fl z , Fl Fl allowinterfaces Ar pattern
				.Op Fl Fl inactive
				.Op interface
				.Op ...
				.Nm
				.Fl n , Fl Fl rebind
				.Op interface
				.Nm
				.Fl k , Fl Fl release
				.Op interface
				.Nm
				.Fl U , Fl Fl dumplease
				.Ar interface
				.Nm
				.Fl Fl version
				.Nm
				.Fl x , Fl Fl exit
				.Op interface
				.Sh DESCRIPTION
				.Nm
				is an implementation of the DHCP client specified in
				.Li RFC 2131 .
				.Nm
				gets the host information
				.Po
				IP address, routes, etc
				.Pc
				from a DHCP server and configures the network
				.Ar interface
				of the
				machine on which it is running.
				.Nm
				then runs the configuration script which writes DNS information to
				.Xr resolvconf 8 ,
				if available, otherwise directly to
				.Pa /etc/resolv.conf .
				If the hostname is currently blank, (null) or localhost, or
				.Va force_hostname
				is YES or TRUE or 1 then
				.Nm
				sets the hostname to the one supplied by the DHCP server.
				.Nm
				then daemonises and waits for the lease renewal time to lapse.
				It will then attempt to renew its lease and reconfigure if the new lease
				changes when the lease begins to expire or the DHCP server sends a message
				to renew early.
				.Pp
				If any interface reports a working carrier then
				.Nm
				will try and obtain a lease before forking to the background,
				otherwise it will fork right away.
				This behaviour can be modified with the
				.Fl b , Fl Fl background
				and
				.Fl w , Fl Fl waitip
				options.
				.Pp
				.Nm
				is also an implementation of the BOOTP client specified in
				.Li RFC 951 .
				.Pp
				.Nm
				is also an implementation of the IPv6 Router Solicitor as specified in
				.Li RFC 4861
				and
				.Li RFC 6106 .
				.Pp
				.Nm
				is also an implementation of the IPv6 Privacy Extensions to AutoConf as
				specified in
				.Li RFC 4941 .
				This feature needs to be enabled in the kernel and
				.Nm
				will start using it.
				.Pp
				.Nm
				is also an implementation of the DHCPv6 client as specified in
				.Li RFC 3315 .
				By default,
				.Nm
				only starts DHCPv6 when instructed to do so by an IPV6 Router Advertisement.
				If no Identity Association is configured,
				then a Non-temporary Address is requested.
				.Ss Local Link configuration
				If
				.Nm
				failed to obtain a lease, it probes for a valid IPv4LL address
				.Po
				aka ZeroConf, aka APIPA
				.Pc .
				Once obtained it restarts the process of looking for a DHCP server to get a
				proper address.
				.Pp
				When using IPv4LL,
				.Nm
				nearly always succeeds and returns an exit code of 0.
				In the rare case it fails, it normally means that there is a reverse ARP proxy
				installed which always defeats IPv4LL probing.
				To disable this behaviour, you can use the
				.Fl L , Fl Fl noipv4ll
				option.
				.Ss Multiple interfaces
				If a list of interfaces are given on the command line, then
				.Nm
				only works with those interfaces, otherwise
				.Nm
				discovers available Ethernet interfaces that can be configured.
				When
				.Nm
				not limited to one interface on the command line,
				it is running in Master mode.
				The
				.Nm dhcpcd-ui
				project expects dhcpcd to be running this way.
				.Pp
				If a single interface is given then
				.Nm
				only works for that interface and runs as a separate instance to other
				.Nm
				processes.
				.Fl w , Fl Fl waitip
				option is enabled in this instance to maintain compatibility with older
				versions.
				Using a single interface also affects the
				.Fl k ,
				.Fl N ,
				.Fl n
				and
				.Fl x
				options, where the same interface will need to be specified, as a lack of an
				interface will imply Master mode which this is not.
				To force starting in Master mode with only one interface, the
				.Fl M , Fl Fl master
				option can be used.
				.Pp
				Interfaces are preferred by carrier, DHCP lease/IPv4LL and then lowest metric.
				For systems that support route metrics, each route will be tagged with the
				metric, otherwise
				.Nm
				changes the routes to use the interface with the same route and the lowest
				metric.
				See options below for controlling which interfaces we allow and deny through
				the use of patterns.
				.Pp
				Non-ethernet interfaces and some virtual ethernet interfaces
				such as TAP and bridge are ignored by default,
				as is the FireWire interface.
				To work with these devices they either need to be specified on the command line,
				be listed in
				.Fl Fl allowinterfaces
				or have an interface directive in
				.Pa @SYSCONFDIR@/dhcpcd.conf .
				.Ss Hooking into events
				.Nm
				runs
				.Pa @SCRIPT@ ,
				or the script specified by the
				.Fl c , Fl Fl script
				option.
				This script runs each script found in
				.Pa @HOOKDIR@
				in a lexical order.
				The default installation supplies the scripts
				.Pa 01-test ,
				.Pa 02-dump ,
				.Pa 20-resolv.conf
				and
				.Pa 30-hostname .
				You can disable each script by using the
				.Fl C , Fl Fl nohook
				option.
				See
				.Xr dhcpcd-run-hooks 8
				for details on how these scripts work.
				.Nm
				currently ignores the exit code of the script.
				.Pp
				More scripts are supplied in
				.Pa @DATADIR@/dhcpcd/hooks
				and need to be copied to
				.Pa @HOOKDIR@
				if you intend to use them.
				For example, you could install
				.Pa 29-lookup-hostname
				so that
				.Nm
				can lookup the hostname of the IP address in DNS if no hostname
				is given by the lease and one is not already set.
				.Ss Fine tuning
				You can fine-tune the behaviour of
				.Nm
				with the following options:
				.Bl -tag -width indent
				.It Fl b , Fl Fl background
				Background immediately.
				This is useful for startup scripts which don't disable link messages for
				carrier status.
				.It Fl c , Fl Fl script Ar script
				Use this
				.Ar script
				instead of the default
				.Pa @SCRIPT@ .
				.It Fl D , Fl Fl duid
				Use a DHCP Unique Identifier.
				If a system UUID is available, that will be used to create a DUID-UUID,
				otheriwse if persistent storage is available then a DUID-LLT
				(link local address + time) is generated,
				otherwise DUID-LL is generated (link local address).
				This, plus the IAID will be used as the
				.Fl I , Fl Fl clientid .
				The DUID generated will be held in
				.Pa @DBDIR@/duid
				and should not be copied to other hosts.
				This file also takes precedence over the above rules.
				.It Fl d , Fl Fl debug
				Echo debug messages to the stderr and syslog.
				.It Fl E , Fl Fl lastlease
				If
				.Nm
				cannot obtain a lease, then try to use the last lease acquired for the
				interface.
				.It Fl Fl lastleaseextend
				Same as the above, but the lease will be retained even if it expires.
				.Nm
				will give it up if any other host tries to claim it for their own via ARP.
				This violates RFC 2131, section 3.7, which states the lease should be
				dropped once it has expired.
				.It Fl e , Fl Fl env Ar value
				Push
				.Ar value
				to the environment for use in
				.Xr dhcpcd-run-hooks 8 .
				For example, you can force the hostname hook to always set the hostname with
				.Fl e
				.Va force_hostname=YES .
				.It Fl g , Fl Fl reconfigure
				.Nm
				will re-apply IP address, routing and run
				.Xr dhcpcd-run-hooks 8
				for each interface.
				This is useful so that a 3rd party such as PPP or VPN can change the routing
				table and / or DNS, etc and then instruct
				.Nm
				to put things back afterwards.
				.Nm
				does not read a new configuration when this happens - you should rebind if you
				need that functionality.
				.It Fl F , Fl Fl fqdn Ar fqdn
				Requests that the DHCP server updates DNS using FQDN instead of just a
				hostname.
				Valid values for
				.Ar fqdn
				are disable, none, ptr and both.
				.Nm
				itself never does any DNS updates.
				.Nm
				encodes the FQDN hostname as specified in
				.Li RFC 1035 .
				.It Fl f , Fl Fl config Ar file
				Specify a config to load instead of
				.Pa @SYSCONFDIR@/dhcpcd.conf .
				.Nm
				always processes the config file before any command line options.
				.It Fl h , Fl Fl hostname Ar hostname
				Sends
				.Ar hostname
				to the DHCP server so it can be registered in DNS.
				If
				.Ar hostname
				is an empty string then the current system hostname is sent.
				If
				.Ar hostname
				is a FQDN (i.e., contains a .) then it will be encoded as such.
				.It Fl I , Fl Fl clientid Ar clientid
				Send the
				.Ar clientid .
				If the string is of the format 01:02:03 then it is encoded as hex.
				For interfaces whose hardware address is longer than 8 bytes, or if the
				.Ar clientid
				is an empty string then
				.Nm
				sends a default
				.Ar clientid
				of the hardware family and the hardware address.
				.It Fl i , Fl Fl vendorclassid Ar vendorclassid
				Override the DHCPv4
				.Ar vendorclassid
				field sent.
				The default is
				dhcpcd-<version>:<os>:<machine>:<platform>.
				For example
				.D1 dhcpcd-5.5.6:NetBSD-6.99.5:i386:i386
				If not set then none is sent.
				Some badly configured DHCP servers reject unknown vendorclassids.
				To work around it, try and impersonate Windows by using the MSFT vendorclassid.
				.It Fl j , Fl Fl logfile Ar logfile
				Writes to the specified
				.Ar logfile
				rather than
				.Xr syslog 3 .
				The
				.Ar logfile
				is reopened when
				.Nm
				receives the
				.Dv SIGUSR2
				signal.
				.It Fl k , Fl Fl release Op Ar interface
				This causes an existing
				.Nm
				process running on the
				.Ar interface
				to release its lease and de-configure the
				.Ar interface
				regardless of the
				.Fl p , Fl Fl persistent
				option.
				If no
				.Ar interface
				is specified then this applies to all interfaces in Master mode.
				If no interfaces are left running,
				.Nm
				will exit.
				.It Fl l , Fl Fl leasetime Ar seconds
				Request a specific lease time in
				.Ar seconds .
				By default
				.Nm
				does not request any lease time and leaves it in the hands of the
				DHCP server.
				.It Fl M , Fl Fl master
				Start
				.Nm
				in Master mode even if only one interface specified on the command line.
				See the Multiple Interfaces section above.
				.It Fl m , Fl Fl metric Ar metric
				Metrics are used to prefer an interface over another one, lowest wins.
				.Nm
				will supply a default metic of 200 +
				.Xr if_nametoindex 3 .
				An extra 100 will be added for wireless interfaces.
				.It Fl n , Fl Fl rebind Op Ar interface
				Notifies
				.Nm
				to reload its configuration and rebind the specified
				.Ar interface .
				If no
				.Ar interface
				is specified then this applies to all interfaces in Master mode.
				If
				.Nm
				is not running, then it starts up as normal.
				.It Fl N , Fl Fl renew Op Ar interface
				Notifies
				.Nm
				to renew existing addresses on the specified
				.Ar interface .
				If no
				.Ar interface
				is specified then this applies to all interfaces in Master mode.
				If
				.Nm
				is not running, then it starts up as normal.
				Unlike the
				.Fl n , Fl Fl rebind
				option above, the configuration for
				.Nm
				is not reloaded.
				.It Fl o , Fl Fl option Ar option
				Request the DHCP
				.Ar option
				variable for use in
				.Pa @SCRIPT@ .
				.It Fl p , Fl Fl persistent
				.Nm
				normally de-configures the
				.Ar interface
				and configuration when it exits.
				Sometimes, this isn't desirable if, for example, you have root mounted over
				NFS or SSH clients connect to this host and they need to be notified of
				the host shutting down.
				You can use this option to stop this from happening.
				.It Fl r , Fl Fl request Ar address
				Request the
				.Ar address
				in the DHCP DISCOVER message.
				There is no guarantee this is the address the DHCP server will actually give.
				If no
				.Ar address
				is given then the first address currently assigned to the
				.Ar interface
				is used.
				.It Fl s , Fl Fl inform Ar address Ns Op Ar /cidr Ns Op Ar /broadcast_address
				Behaves like
				.Fl r , Fl Fl request
				as above, but sends a DHCP INFORM instead of DISCOVER/REQUEST.
				This does not get a lease as such, just notifies the DHCP server of the
				.Ar address
				in use.
				You should also include the optional
				.Ar cidr
				network number in case the address is not already configured on the interface.
				.Nm
				remains running and pretends it has an infinite lease.
				.Nm
				will not de-configure the interface when it exits.
				If
				.Nm
				fails to contact a DHCP server then it returns a failure instead of falling
				back on IPv4LL.
				.It Fl Fl inform6
				Performs a DHCPv6 Information Request.
				No address is requested or specified, but all other DHCPv6 options are allowed.
				This is normally performed automatically when the IPv6 Router Advertises
				that the client should perform this operation.
				This option is only needed when
				.Nm
				is not processing IPv6RA messages and the need for DHCPv6 Information Request
				exists.
				.It Fl S , Fl Fl static Ar value
				Configures a static DHCP
				.Ar value .
				If you set
				.Ic ip_address
				then
				.Nm
				will not attempt to obtain a lease and just use the value for the address with
				an infinite lease time.
				.Pp
				Here is an example which configures a static address, routes and DNS.
				.D1 dhcpcd -S ip_address=192.168.0.10/24 \e
				.D1 -S routers=192.168.0.1 \e
				.D1 -S domain_name_servers=192.168.0.1 \e
				.D1 eth0
				.Pp
				You cannot presently set static DHCPv6 values.
				Use the
				.Fl e , Fl Fl env
				option instead.
				.It Fl t , Fl Fl timeout Ar seconds
				Timeout after
				.Ar seconds ,
				instead of the default 30.
				A setting of 0
				.Ar seconds
				causes
				.Nm
				to wait forever to get a lease.
				If
				.Nm
				is working on a single interface then
				.Nm
				will exit when a timeout occurs, otherwise
				.Nm
				will fork into the background.
				.It Fl u , Fl Fl userclass Ar class
				Tags the DHCPv4 message with the userclass
				.Ar class .
				DHCP servers use this to give members of the class DHCP options other than the
				default, without having to know things like hardware address or hostname.
				.It Fl v , Fl Fl vendor Ar code , Ns Ar value
				Add an encapsulated vendor option.
				.Ar code
				should be between 1 and 254 inclusive.
				To add a raw vendor string, omit
				.Ar code
				but keep the comma.
				Examples.
				.Pp
				Set the vendor option 01 with an IP address.
				.D1 dhcpcd \-v 01,192.168.0.2 eth0
				Set the vendor option 02 with a hex code.
				.D1 dhcpcd \-v 02,01:02:03:04:05 eth0
				Set the vendor option 03 with an IP address as a string.
				.D1 dhcpcd \-v 03,\e"192.168.0.2\e" eth0
				Set un-encapsulated vendor option to hello world.
				.D1 dhcpcd \-v ,"hello world" eth0
				.It Fl Fl version
				Display both program version and copyright information.
				.Nm
				then exits before doing any configuration.
				.It Fl w
				Wait for an address to be assigned before forking to the background.
				Does not take an argument, unlike the below option.
				.It Fl Fl waitip Ns = Ns Op 4 \| 6
				Wait for an address to be assigned before forking to the background.
				4 means wait for an IPv4 address to be assigned.
				6 means wait for an IPv6 address to be assigned.
				If no argument is given,
				.Nm
				will wait for any address protocol to be assigned.
				It is possible to wait for more than one address protocol and
				.Nm
				will only fork to the background when all waiting conditions are satisfied.
				.It Fl x , Fl Fl exit Op Ar interface
				This will signal an existing
				.Nm
				process running on the
				.Ar interface
				to exit.
				If no
				.Ar interface
				is specified, then the above is applied to all interfaces in Master mode.
				See the
				.Fl p , Fl Fl persistent
				option to control configuration persistence on exit,
				which is enabled by default in
				.Xr dhcpcd.conf 5 .
				.Nm
				then waits until this process has exited.
				.It Fl y , Fl Fl reboot Ar seconds
				Allow
				.Ar reboot
				seconds before moving to the discover phase if we have an old lease to use.
				Allow
				.Ar reboot
				seconds before starting fallback states from the discover phase.
				IPv4LL is started when the first
				.Ar reboot
				timeout is reached.
				The default is 5 seconds.
				A setting of 0 seconds causes
				.Nm
				to skip the reboot phase and go straight into discover.
				This has no effect on DHCPv6 other than skipping the reboot phase.
				.El
				.Ss Restricting behaviour
				.Nm
				will try to do as much as it can by default.
				However, there are sometimes situations where you don't want the things to be
				configured exactly how the DHCP server wants.
				Here are some options that deal with turning these bits off.
				.Pp
				Note that when
				.Nm
				is restricted to a single interface then the interface also needs to be
				specified when asking
				.Nm
				to exit using the commandline.
				If the protocol is restricted as well then the protocol needs to be included
				with the exit instruction.
				.Bl -tag -width indent
				.It Fl 1 , Fl Fl oneshot
				Exit after configuring an interface.
				Use the
				.Fl w , Fl Fl waitip
				option to specify which protocol(s) to configure before exiting.
				.It Fl 4 , Fl Fl ipv4only
				Configure IPv4 only.
				.It Fl 6 , Fl Fl ipv6only
				Configure IPv6 only.
				.It Fl A , Fl Fl noarp
				Don't request or claim the address by ARP.
				This also disables IPv4LL.
				.It Fl B , Fl Fl nobackground
				Don't run in the background when we acquire a lease.
				This is mainly useful for running under the control of another process, such
				as a debugger or a network manager.
				.It Fl C , Fl Fl nohook Ar script
				Don't run this hook script.
				Matches full name, or prefixed with 2 numbers optionally ending with
				.Pa .sh .
				.Pp
				So to stop
				.Nm
				from touching your DNS settings you would do:-
				.D1 dhcpcd -C resolv.conf eth0
				.It Fl G , Fl Fl nogateway
				Don't set any default routes.
				.It Fl H , Fl Fl xidhwaddr
				Use the last four bytes of the hardware address as the DHCP xid instead
				of a randomly generated number.
				.It Fl J , Fl Fl broadcast
				Instructs the DHCP server to broadcast replies back to the client.
				Normally this is only set for non-Ethernet interfaces,
				such as FireWire and InfiniBand.
				In most instances,
				.Nm
				will set this automatically.
				.It Fl K , Fl Fl nolink
				Don't receive link messages for carrier status.
				You should only have to use this with buggy device drivers or running
				.Nm
				through a network manager.
				.It Fl L , Fl Fl noipv4ll
				Don't use IPv4LL (aka APIPA, aka Bonjour, aka ZeroConf).
				.It Fl O , Fl Fl nooption Ar option
				Removes the
				.Ar option
				from the DHCP message before processing.
				.It Fl P , Fl Fl printpidfile
				Print the
				.Pa pidfile
				.Nm
				will use based on commmand-line arguments to stdout.
				.It Fl Q , Fl Fl require Ar option
				Requires the
				.Ar option
				to be present in all DHCP messages, otherwise the message is ignored.
				To enforce that
				.Nm
				only responds to DHCP servers and not BOOTP servers, you can
				.Fl Q
				.Ar dhcp_message_type .
				.It Fl q , Fl Fl quiet
				Quiet
				.Nm
				on the command line, only warnings and errors will be displayed.
				The messages are still logged though.
				.It Fl T , Fl Fl test
				On receipt of DHCP messages just call
				.Pa @SCRIPT@
				with the reason of TEST which echos the DHCP variables found in the message
				to the console.
				The interface configuration isn't touched and neither are any configuration
				files.
				The
				.Ar rapid_commit
				option is not sent in TEST mode so that the server does not lease an address.
				To test INFORM the interface needs to be configured with the desired address
				before starting
				.Nm .
				.It Fl U , Fl Fl dumplease Ar interface
				Dumps the last lease for the
				.Ar interface
				to stdout.
				If omitted, standard input is used to read a DHCP wire formatted message.
				Use the
				.Fl 4
				or
				.Fl 6
				flags to specify an address family.
				.It Fl V , Fl Fl variables
				Display a list of option codes, the associated variable and encoding for use in
				.Xr dhcpcd-run-hooks 8 .
				Variables are prefixed with new_ and old_ unless the option number is -.
				Variables without an option are part of the DHCP message and cannot be
				directly requested.
				.It Fl W , Fl Fl whitelist Ar address Ns Op /cidr
				Only accept packets from
				.Ar address Ns Op /cidr .
				.Fl X , Fl Fl blacklist
				is ignored if
				.Fl W , Fl Fl whitelist
				is set.
				.It Fl X , Fl Fl blacklist Ar address Ns Op Ar /cidr
				Ignore all packets from
				.Ar address Ns Op Ar /cidr .
				.It Fl Z , Fl Fl denyinterfaces Ar pattern
				When discovering interfaces, the interface name must not match
				.Ar pattern
				which is a space or comma separated list of patterns passed to
				.Xr fnmatch 3 .
				.It Fl z , Fl Fl allowinterfaces Ar pattern
				When discovering interfaces, the interface name must match
				.Ar pattern
				which is a space or comma separated list of patterns passed to
				.Xr fnmatch 3 .
				If the same interface is matched in
				.Fl Z , Fl Fl denyinterfaces
				then it is still denied.
				.It Fl Fl inactive
				Don't start any interfaces other than those specified on the command line.
				This allows
				.Nm
				to be started in Master mode and then wait for subsequent
				.Nm
				commands to start each interface as required.
				.It Fl Fl nodev
				Don't load any
				.Pa /dev
				management modules.
				.El
				.Sh 3RDPARTY LINK MANAGEMENT
				Some interfaces require configuration by 3rd parties, such as PPP or VPN.
				When an interface configuration in
				.Nm
				is marked as STATIC or INFORM without an address then
				.Nm
				will monitor the interface until an address is added or removed from it and
				act accordingly.
				For point to point interfaces (like PPP), a default route to its
				destination is automatically added to the configuration.
				If the point to point interface is configured for INFORM, then
				.Nm
				unicasts INFORM to the destination, otherwise it defaults to STATIC.
				.Sh NOTES
				.Nm
				requires a Berkley Packet Filter, or BPF device on BSD based systems and a
				Linux Socket Filter, or LPF device on Linux based systems for all IPv4
				configuration.
				.Pp
				If restricting
				.Nm
				to a single interface and optionally address family via the command-line
				then all further calls to
				.Nm
				to rebind, reconfigure or exit need to include the same restrictive flags
				so that
				.Nm
				knows which process to signal.
				.Pp
				Some DHCP servers implement ClientID filtering.
				If
				.Nm
				is replacing an in-use DHCP client then you might need to adjust the clientid
				option
				.Nm
				sends to match.
				If using a DUID in place of the ClientID, edit
				.Pa @DBDIR@/duid
				accordingly.
				.Sh FILES
				.Bl -ohang
				.It Pa @SYSCONFDIR@/dhcpcd.conf
				Configuration file for dhcpcd.
				If you always use the same options, put them here.
				.It Pa @SCRIPT@
				Bourne shell script that is run to configure or de-configure an interface.
				.It Pa @LIBDIR@/dhcpcd/dev
				Linux
				.Pa /dev
				management modules.
				.It Pa @HOOKDIR@
				A directory containing bourne shell scripts that are run by the above script.
				Each script can be disabled by using the
				.Fl C , Fl Fl nohook
				option described above.
				.It Pa @DBDIR@/duid
				Text file that holds the DUID used to identify the host.
				.It Pa @DBDIR@/secret
				Text file that holds a secret key known only to the host.
				.It Pa @DBDIR@/ Ns Ar interface Ns Ar -ssid Ns .lease
				The actual DHCP message sent by the server.
				We use this when reading the last
				lease and use the file's mtime as when it was issued.
				.It Pa @DBDIR@/ Ns Ar interface Ns Ar -ssid Ns .lease6
				The actual DHCPv6 message sent by the server.
				We use this when reading the last
				lease and use the file's mtime as when it was issued.
				.It Pa @DBDIR@/rdm_monotonic
				Stores the monotonic counter used in the
				.Ar replay
				field in Authentication Options.
				.It Pa @RUNDIR@/dhcpcd.pid
				Stores the PID of
				.Nm
				running on all interfaces.
				.It Pa @RUNDIR@/dhcpcd\- Ns Ar interface Ns .pid
				Stores the PID of
				.Nm
				running on the
				.Ar interface .
				.It Pa @RUNDIR@/dhcpcd.sock
				Control socket to the master daemon.
				.It Pa @RUNDIR@/dhcpcd.unpriv.sock
				Unprivileged socket to the master daemon, only allows state retrieval.
				.It Pa @RUNDIR@/dhcpcd\- Ns Ar interface Ns .sock
				Control socket to per interface daemon.
				.El
				.Sh SEE ALSO
				.Xr fnmatch 3 ,
				.Xr if_nametoindex 3 ,
				.Xr dhcpcd.conf 5 ,
				.Xr resolv.conf 5 ,
				.Xr dhcpcd-run-hooks 8 ,
				.Xr resolvconf 8
				.Sh STANDARDS
				RFC\ 951, RFC\ 1534, RFC\ 2104, RFC\ 2131, RFC\ 2132, RFC\ 2563, RFC\ 2855,
				RFC\ 3004, RFC\ 3118, RFC\ 3203, RFC\ 3315, RFC\ 3361, RFC\ 3633, RFC\ 3396,
				RFC\ 3397, RFC\ 3442, RFC\ 3495, RFC\ 3925, RFC\ 3927, RFC\ 4039, RFC\ 4075,
				RFC\ 4242, RFC\ 4361, RFC\ 4390, RFC\ 4702, RFC\ 4074, RFC\ 4861, RFC\ 4833,
				RFC\ 4941, RFC\ 5227, RFC\ 5942, RFC\ 5969, RFC\ 6106, RFC\ 6334, RFC\ 6355,
				RFC\ 6603, RFC\ 6704, RFC\ 7217, RFC\ 7550.
				.Sh AUTHORS
				.An Roy Marples Aq Mt roy@marples.name
				.Sh BUGS
				Please report them to
				.Lk http://roy.marples.name/projects/dhcpcd