NDPD(1M)NDPD(1M)NAMEndpd - IPv6 Neighbor Discovery daemon
SYNOPSIS
/usr/etc/ndpd [-dipqrstvMO] [-I <if>]
[-D <max>[/<min>[/<life>]]] [-N <n>]
[-P [<invlife>]/[<deplife>]]
[-T [<reachtim>]/[<retrans>]/[<hlim>]]
DESCRIPTIONndpd is a daemon invoked at boot time to perform IPv6 neighbor discovery
for the automatic configuration of link-local addresses and to
automatically configure global addresses when router advertisements are
received from an IPv6 aware router.
ndpd is normally started by the network start-up script during boot and
is run with the options contained in /etc/config/ndpd.options. When it
starts, it first starts the neighbor discovery protocol (RFC 2461) on
each interface by choosing a link-local address and sending a neighbor
solication message to check that the address is unique for that
interface. It also sends out router solication messages on each
interface. When a router advertisment message is received, it will try
and configure a global address on that interface using the prefix
contained in the message.
The main program supports a number of command line options to specify
Neighbor Discovery routing policy and to set debug and general options.
The specific options are:
-d Enable debugging (exceptional conditions and dump)
-D <max>[/<min>[/<life>]]
Set Unsolicited Router Advertisements intervals in seconds. Default
is 600 seconds. The valid range is [4,1800] seconds
-i Ignore all router advertisements. This use of this option prevents
autoconfiguration of IPv6 global addresses using prefixes learned
from router advertisements, which could cause the system to be
unreachable (via IPv6.) Therefore, the use of this option is
strongly discouraged. But if you wish to configure IPv6 global
addresses manually (and forgo the benefit of autoconfiguration of
IPv6 global addresses) this option allows for that.
-I <if>
Specify the default interface for link local unicast and multicast
destinations. Routes to fe80::/10 and ff02::/16 will be placed on
the interface named <if>.
-M Set M flag (stateful configuration) in Router Advertisements
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NDPD(1M)NDPD(1M)-N <n>
Number of Duplicate Address Detection Transmits. Overrides the
default value of 1 as per the Address Configuration Specification.
The maximum number of Duplicate Address Detection Transmits is 8.
The minimum value, 0, suppresses Duplicate Address Detection.
-O Set O flag (other stateful) in Router Advertisements
-q Client mode. The daemon will receive but not send ND router
advertisements.
-p Don't send prefixes within router advertisements and ignore prefixes
received in router advertisements. Prefixes will be determined from
the interface configuration.
-P [invlife]/[deplife]
Set the invalid life value and the deprecated life value for
announced prefixes, in seconds. The default value is 0xffffffff
(infinite)
-r DO NOT offer to be the default router in Router Advertisments
-s Server mode. The daemon will send ND router advertisements.
-t Add timestamps to all logged messages
-T [<reachtim>]/[<retrans>]/[<hlim>]
Set BaseReachableTime to specified value in seconds. If <reachim>
is not zero then sets the BaseReachableTime to <reachim> seconds.
If <retrans> is not zero then sets RetransTime to <retrans>
seconds. If <hlim> is not zero, then sets the hop limit field in
router advertisement messages to <hlim>.
-v Enable verbose output. Logs interesting events to system loggin
daemon and to console.
ndpd reads additional configuration information from /etc/ndpd.conf .
This file can be modified while the program is running as changes are
checked before any emission or reception of packets or on reception of a
HUP signal (see kill(1)).
The file contains directives, one per line (with # as comment). All the
IPv6 addresses and prefixes in the file must be in numeric form. No
symbolic name are supported, except for the gateway directive. Each line
begins with a keyword and is made of options of the form
keyword key = arguments
where the 'arguments' are separated by spaces.
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NDPD(1M)NDPD(1M)
Per-interface directives are:
mtu [=<mtuval>]
Advertise a MTU value of <mtuval> in router advertisments. If there
is no <mtuval> argument, the advertised MTU is the MTU of the
interface. If <mtuval> is 0 then suppress the advertisment of MTU.
rtadv=(n|y|<min>[/<max>])
Do not send (send) router advertisments. With min[/max] option, set
the interval between router advertisments.
flag=[MO]
Set the stateful mode flags in router advertisments. M means ``use
stateful configuration''. O means ``use stateful configuration, but
not for addresses''.
life = <dd>
Set router life field in router advertisments(value in seconds).
reach = <dd>
Set reachable field in router advertisments (value in seconds)
retrans = <dd>
Set retransmit interval field in router advertisments (value in
seconds).
If the right hand side of <interface> = <list>, where <list> is comma-
separated, there are two possibilities. If there is no keyword, the
option directive is a default option. If there is an <interface> field,
the option parameters apply only to the listed interfaces (the list must
comma-seperated). One can use 'le*' to match all the 'leX' interfaces.
The default option must be the first line in the /etc/ndpd.conf file.
Prefix directive
The prefix directive defines the prefixes announced in Router
advertisement directives. If there is no prefix directive for an
interface, the router advertisment contains the list of prefixes deduced
from the address list of the interface. If there are prefix directives,
the router advertisment contains the list of prefixes defined by the
different prefix directives (in order). No prefix is installed in the
kernel. If there is one directive of the form prefix=none, no prefix list
is advertised.
The possible prefix directives are:
prefix = <xxx>::/<dd>
Set the advertised prefix
flag = [LA]
Set the L and/or A flag for the prefix (the default is LA).
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deprec = <dd>
Set the deprecated time for the prefix (value in seconds).
valid = <dd>
Set the validity time for the prefix (value in seconds).
<if> = <interface>
Specify the <interface> name on which the directive applies. This
is MANDATORY.
FILES
/etc/config/ndpd.options Site-dependent options
/etc/ndpd.conf ndpd configuration file
SEE ALSOndp(1M), ndp(7P), ipv6(7M)
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