Control the IPv6 Neighbor Discovery Protocol


ndp -A wait [-ntl]
ndp -a [-ntl]
ndp -c [-nt]
ndp -d [-nt] hostname
ndp -f [-nt] filename
ndp -H
ndp -I [delete|interface]
ndp -i interface [flags...]
ndp -P
ndp -p
ndp -R
ndp -r
ndp -s [-nt] nodename ether_addr [temp] [proxy]

Runs on:

QNX Neutrino


-A wait
Repeat -a (dump NDP entries) every wait seconds.
Dump the existing NDP entries.
Erase all NDP entries.
-d hostname
Delete the NDP entry for this hostname.
-f filename
Parse the file specified by filename.
Harmonize consistency between the routing table and the default router list; install the top entry of the list into the kernel routing table.
-I [delete|interface]
Show or specify the default interface that's to be used as the default route when there's no default router.
Option: Action:
-I Show the current default interface.
-I delete Delete the current interface from the kernel.
-I interface Use this interface as the default.
-i interface [flags...]
View the neighbor discovery (ND) information for this interface. If flags is specified, set or clear the flag(s) associated with this interface. A flag is cleared if it starts with a hyphen (-). For example, to disable IPv6 on an interface:
ndp -i interface disabled

To re-enable IPv6 on an interface:

ndp -i interface -- -disabled

The supported flags include:

  • nud — toggle Neighbor Unreachability Detection on the interface (the default is on)
  • accept_rtadv — specify whether or not to accept Router Advertisement messages received on the interface
  • auto_linklocal — specify whether or not to perform automatic link-local address configuration on interface
  • override_rtadv — specify whether or not to override the net.inet6.ip6.accept_rtadv variable
  • prefer_source — prefer addresses on the interface as candidates of the source address for outgoing packets
  • disabled — disable IPv6 operation on the interface
  • basereachable=number — specify the BaseReachbleTimer on the interface in milliseconds.
  • retrans=number — specify the RetransTimer on the interface in milliseconds.
  • curhlim=number — specify the Cur Hop Limit on the interface
Don't try to resolve a numeric address to a hostname.
Flush all the entries in the prefix list.
Show the prefix list.
Flush all the entries in the default router list.
Show the default router list.
-s nodename ether_addr [temp] [proxy]
Register a permanent NDP entry for this node (use temp to register a temporary entry). If you specify proxy, the system acts as a proxy NDP server that responds to requests for hostname even though the host address is not its own.


This utility manipulates the address mapping table used by the Neighbor Discovery Protocol (NDP).

Exit status:

Successful completion.
An error occurred.