RTADVD(8) OpenBSD System Manager's Manual RTADVD(8)NAMErtadvd - router advertisement daemon
SYNOPSISrtadvd [-dMRs] [-c configfile] interface ...
DESCRIPTIONrtadvd sends router advertisement packets to the specified interfaces.
The program will daemonize itself on invocation. It will then send
router advertisement packets periodically, as well as in response to
router solicitation messages sent by end hosts.
Router advertisements can be configured on a per-interface basis, as
described in rtadvd.conf(5).
If there is no configuration file entry for an interface, or if the
configuration file does not exist at all, rtadvd sets all the parameters
to their default values. In particular, rtadvd reads all the interface
routes from the routing table and advertises them as on-link prefixes.
rtadvd also watches the routing table. By default, if an interface
direct route is added/deleted on an advertising interface and no static
prefixes are specified by the configuration file, rtadvd adds/deletes the
corresponding prefix to/from its advertising list, respectively. The -s
option may be used to disable this behavior. Moreover, if the status of
an advertising interface changes, rtadvd will start or stop sending
router advertisements according to the latest status.
Basically, hosts MUST NOT send Router Advertisement messages at any time
(RFC 2461, Section 6.2.3). However, it would sometimes be useful to
allow hosts to advertise some parameters such as prefix information and
link MTU. Thus, rtadvd can be invoked if router lifetime is explicitly
set to zero on every advertising interface.
The command line options are:
-c configfile
Specify an alternate location, configfile, for the configuration
file. By default, /etc/rtadvd.conf is used.
-d Do not daemonize. If this option is specified, rtadvd will run
in the foreground and log to stderr.
-M Specify an interface to join the all-routers site-local multicast
group. By default, rtadvd tries to join the first advertising
interface appearing on the command line. This option has meaning
only with the -R option, which enables routing renumbering
protocol support.
-R Accept router renumbering requests. If you enable it, an
ipsec(4) setup is suggested for security reasons. This option is
currently disabled, and is ignored by rtadvd with a warning
message.
-s Do not add or delete prefixes dynamically. Only statically
configured prefixes, if any, will be advertised.
Upon receipt of signal SIGUSR1, rtadvd will dump the current internal
state into syslog(3).
Use SIGTERM to kill rtadvd gracefully. In this case, rtadvd will
transmit router advertisement with router lifetime 0 to all the
interfaces (in accordance with RFC 2461 6.2.5).
FILES
/etc/rtadvd.conf The default configuration file.
/var/run/rtadvd.pid Contains the PID of the currently running rtadvd.
EXIT STATUS
The rtadvd utility exits 0 on success, and >0 if an error occurs.
SEE ALSOrtadvd.conf(5), rtsol(8), syslogd(8)HISTORY
The rtadvd command first appeared in the WIDE Hydrangea IPv6 protocol
stack kit.
BUGS
There used to be some text that recommended users not to let rtadvd
advertise Router Advertisement messages on an upstream link to avoid
undesirable icmp6(4) redirect messages. However, based on later
discussion in the IETF IPng working group, all routers should rather
advertise the messages regardless of the network topology, in order to
ensure reachability.
OpenBSD 4.9 September 3, 2010 OpenBSD 4.9
