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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:



-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 the special character -. Possible flags are:
Toggle NUD (Neighbor Unreachability Detection) on the interface (default is on).
Don't truncate the numeric IPv6 addresses.
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.
Print a timestamp on each entry so that it's possible to merge the output with tcpdump. Typically used with -A.


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

Exit status:

Successful completion.
An error occurred.

See also: