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NetBSD 6.1.5 - man page for dhcpcd.conf (netbsd section 5)

DHCPCD.CONF(5)			     System Manager's Manual			   DHCPCD.CONF(5)

     dhcpcd.conf -- dhcpcd configuration file

     Although dhcpcd can do everything from the command line, there are cases where it's just
     easier to do it once in a configuration file.  Most of the options found in dhcpcd(8) can be
     used here.  The first word on the line is the option and the rest of the line is the value.
     Leading and trailing whitespace for the option and value are trimmed.  You can escape char-
     acters in the value using the \ character.

     Blank lines and lines starting with # are ignored.

     Here's a list of available options:

     allowinterfaces pattern
	     When discovering interfaces, the interface name must match pattern which is a space
	     or comma separated list of patterns passed to fnmatch(3).	If the same interface is
	     matched in denyinterfaces then it is still denied.

     denyinterfaces pattern
	     When discovering interfaces, the interface name must not match pattern which is a
	     space or comma separated list of patterns passed to fnmatch(3).

     arping address [address]
	     dhcpcd will arping each address in order before attempting DHCP.  If an address is
	     found, we will select the replying hardware address as the profile, otherwise the ip
	     address.  Example:

		   interface bge0

		   static ip_address=

	     Background immediately.  This is useful for startup scripts which don't disable link
	     messages for carrier status.

     blacklist address[/cidr]
	     Ignores all packets from address[/cidr].

     whitelist address[/cidr]
	     Only accept packets from address[/cidr].  blacklist is ignored if whitelist is set.

	     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
	     cases, dhcpcd will set this automatically.

     env value
	     Push value to the environment for use in dhcpcd-run-hooks(8).  For example, you can
	     force the hostname hook to always set the hostname with env force_hostname=YES.

     clientid string
	     Send the 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
	     clientid is an empty string then dhcpcd sends a default clientid of the hardware
	     family and the hardware address.

     duid    Generate an RFC 4361.  compliant clientid.  This requires persistent storage and not
	     all DHCP servers work with it so it's not enabled by default.  The duid generated
	     will be held in /etc/dhcpcd.duid and should not be copied to other hosts.

     fallback profile
	     Fallback to using this profile if DHCP fails.  This allows you to configure a static
	     profile instead of using ZeroConf.

     hostname name
	     Sends hostname to the DHCP server so it can be registered in DNS.	If hostname is an
	     empty string then the current system hostname is sent.  If hostname is a FQDN (ie,
	     contains a .) then it will be encoded as such.

     fqdn [none | ptr | both]
	     none disables FQDN encoding, ptr just asks the DHCP server to update the PTR record
	     of the host in DNS whereas both also updates the A record.  dhcpcd itself never does
	     any DNS updates.  dhcpcd encodes the FQDN hostname as specified in RFC1035.

     interface interface
	     Subsequent options are only parsed for this interface.

	     By default, when dhcpcd receives an IPv6 RA, dhcpcd will only fork to the background
	     if the RA contains at least one unexpired RDNSS option.  Set this option so to make
	     dhcpcd always fork on an RA.

     ic ipv6ra_own
	     Disables kernel IPv6 Router Advertisment processing so dhcpcd can manage addresses
	     and routes.

     ic ipv6ra_own_default
	     Each time dhcpcd receives an IPv6 Router Adveristment, dhcpcd will manage the
	     default route only.  This allows dhcpcd to prefer an interface for outbound traffic
	     based on metric and/or user selection rather than the kernel.

     ic ipv6rs
	     Enables IPv6 Router Advertisment solicitation.  This is on by default, but is docu-
	     mented here in the case where it is disabled globally but needs to be enabled for
	     one interface.

     leasetime seconds
	     Request a leasetime of seconds.

     metric metric
	     Metrics are used to prefer an interface over another one, lowest wins.  dhcpcd will
	     supply a default metric of 200 + if_nametoindex(3).  An extra 100 will be added for
	     wireless interfaces.

     noarp   Don't send any ARP requests.  This also disables IPv4LL.

	     Don't install any default routes.

     nohook script
	     Don't run this hook script.  Matches full name, or prefixed with 2 numbers option-
	     ally ending with .sh.

	     So to stop dhcpcd from touching your DNS or MTU settings you would do:-
		   nohook resolv.conf, mtu

	     Don't attempt to obtain an IPv4LL address if we failed to get one via DHCP.  See RFC

	     Disable solicition of IPv6 Router Advertisements.

     nolink  Don't receive link messages about carrier status.	You should only set this for
	     buggy interface drivers.

     option option
	     Requests the option from the server.  It can be a variable to be used in
	     dhcpcd-run-hooks(8) or the numerical value.  You can specify more options separated
	     by commas, spaces or more option lines.

     nooption option
	     Remove the option from the DHCP message.  This should only be used when a DHCP
	     server sends a non requested option that should not be processed.

     destination option
	     If dhcpcd.conf detects an address added to a point to point interface (PPP, TUN,
	     etc) then it will set the listed DHCP options to the destination address of the

     profile name
	     Subsequent options are only parsed for this profile name.

     quiet   Suppress any dhcpcd output to the console, except for errors.

     reboot seconds
	     Allow reboot seconds before moving to the discover phase if we have an old lease to
	     use.  The default is 5 seconds.  A setting if 0 seconds causes dhcpcd to skip the
	     reboot phase and go straight into discover.

	     dhcpcd will release the lease prior to stopping the interface.

     require option
	     Requires the option to be present in all DHCP messages, otherwise the message is
	     ignored.  It can be a variable to be used in dhcpcd-run-hooks(8) or the numerical
	     value.  You can specify more options separated by commas, spaces or more require
	     lines.  To enforce that dhcpcd only responds to DHCP servers and not BOOTP servers,
	     you can require dhcp_message_type.

     script script
	     Use script instead of the default /libexec/dhcpcd-run-hooks.

     ssid ssid
	     Subsequent options are only parsed for this wireless ssid.

     static value
	     Configures a static value.  If you set ip_address then dhcpcd will not attempt to
	     obtain a lease and just use the value for the address with an infinite lease time.

	     Here is an example which configures a static address, routes and dns.
		   interface eth0
		   static ip_address=
		   static routers=
		   static domain_name_servers=

	     Here is an example for PPP which gives the destination a default route.  It uses the
	     special destination keyword to insert the destination address into the value.
		   interface ppp0
		   static ip_address=
		   destination routers

     timeout seconds
	     The default timeout for waiting for a DHCP response is 30 seconds which may be too
	     long or too short and can be changed here.

     userclass string
	     Tag the DHCP messages with the userclass.	You can specify more than one.

     vendor code,value
	     Add an encapsulated vendor option.  code should be between 1 and 254 inclusive.  To
	     add a raw vendor string, omit code but keep the comma.  Examples.

	     Set the vendor option 01 with an IP address.
		   vendor 01,
	     Set the vendor option 02 with a hex code.
		   vendor 02,01:02:03:04:05
	     Set the vendor option 03 with an IP address as a string.
		   vendor 03,\"\"
	     Set un-encapsulated vendor option to hello world.
		   vendor ,"hello world"

     vendorclassid string
	     The default is dhcpcd-<version>:<os>:<machine>:<platform>.  For example
	     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

     waitip  Wait for an address to be assigned before forking to the background.

	     Use the last four bytes of the hardware address as the DHCP xid instead of a ran-
	     domly generated number.

     dhcpcd-run-hooks(8), dhcpcd(8), if_nametoindex(3), fnmatch(3)

     Roy Marples <roy@marples.name>

     Please report them to

BSD					   May 21, 2012 				      BSD

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