IPv6 Administration Guide

in.ndpd Daemon

This daemon implements router discovery. The daemon also implements auto-address configuration for IPv6. The following table shows the supported options.

Table 3–2 in.ndpd Daemon Options




Turns on debugging for all events 


Turns on specific debugging 


File to read configuration from, instead of default file 


Prints related information for each interface 


Does not loop back router advertisements 


Ignores received packets 


Verbose mode, reports various types of diagnostic messages 


Turns on packet tracing 

Parameters control the actions in.ndpd. Those parameters are set in the /etc/inet/ndpd.conf configuration file and the /var/inet/ndpd_state.interface startup file, if the parameters exist).

When the /etc/inet/ndpd.conf file exists, the file is parsed and used to configure a node as a router. The following table lists the valid keywords that might appear in this file. When a host is booted, routers might not be immediately available. Advertised packets by the router might be dropped. Also, advertised packets might not reach the host. The /var/inet/ndpd_state.interface file is a state file. This file is updated periodically by each node. When the node fails and is restarted, the node can configure its interfaces in the absence of routers. This file contains the interface address, the time that the file is updated, and how long the file is valid. This file also contains other parameters that are “learned” from previous router advertisements.

Note –

You do not need to alter the contents of the state files. The in.ndpd daemon automatically maintains the state files.

Table 3–3 /etc/inet/ndpd.conf Keywords




Specifies router behavior for all interfaces. Use the following syntax to set router parameters and corresponding values: 

ifdefault [variable value]


Specifies the default behavior for prefix advertisements. Use the following syntax to set router parameters and corresponding values: 

prefixdefault [variable value]


Sets per-interface parameters. Use the following syntax: 

if interface [variable value]


Advertises per-interface prefix information. Use the following syntax: 

prefix prefix/length interface [variable value]

Note –

The ifdefault and prefixdefault entries must precede the if and prefix entries in the configuration file.

See the in.ndpd(1M) man page and see also the ndpd.conf(4) man page for a list of configuration variables and allowable values.

Example—/etc/inet/ndpd.conf File

The following example provides a template of commented lines and also shows an example of how the keywords and configuration variables are used.

# ifdefault      [variable value]*
# prefixdefault [variable value]*
# if ifname   [variable value]*
# prefix prefix/length ifname
#  Per interface configuration variables
# Per Prefix:  AdvPrefixList configuration variables

ifdefault AdvReachableTime 30000 AdvRetransTimer 2000
prefixdefault AdvValidLifetime 240m AdvPreferredLifetime 120m

if qe0 AdvSendAdvertisements 1
prefix 2:0:0:56::/64 qe0
prefix fec0:0:0:56::/64 qe0

if qe1 AdvSendAdvertisements 1
prefix 2:0:0:55::/64 qe1
prefix fec0:0:0:56::/64 qe1

if qe2 AdvSendAdvertisements 1
prefix 2:0:0:54::/64 qe2
prefix fec0:0:0:54::/64 qe2