xref: /freebsd/usr.sbin/rtsold/rtsold.8 (revision 4b9d6057)
1.\"	$KAME: rtsold.8,v 1.20 2003/04/11 12:46:12 jinmei Exp $
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30.Dd May 2, 2023
31.Dt RTSOLD 8
32.Os
33.\"
34.Sh NAME
35.Nm rtsold , rtsol
36.Nd router solicitation daemon
37.\"
38.Sh SYNOPSIS
39.Nm
40.Op Fl dDfFimu1
41.Op Fl M Ar script-name
42.Op Fl O Ar script-name
43.Op Fl A Ar script-name
44.Op Fl p Ar pidfile
45.Op Fl R Ar script-name
46.Ar interface ...
47.Nm
48.Op Fl dDfFimu1
49.Op Fl M Ar script-name
50.Op Fl O Ar script-name
51.Op Fl A Ar script-name
52.Op Fl p Ar pidfile
53.Op Fl R Ar script-name
54.Fl a
55.Nm rtsol
56.Op Fl dDiu
57.Op Fl M Ar script-name
58.Op Fl O Ar script-name
59.Op Fl A Ar script-name
60.Op Fl R Ar script-name
61.Ar interface ...
62.Nm rtsol
63.Op Fl dDiu
64.Op Fl M Ar script-name
65.Op Fl O Ar script-name
66.Op Fl A Ar script-name
67.Op Fl R Ar script-name
68.Fl a
69.\"
70.Sh DESCRIPTION
71.Nm
72is the daemon program to send ICMPv6 Router Solicitation messages
73on the specified interfaces.
74If a node (re)attaches to a link,
75.Nm
76sends some Router Solicitations on the link destined to the link-local scope
77all-routers multicast address to discover new routers
78and to get non link-local addresses.
79.Pp
80.Nm
81should be used on IPv6 hosts
82.Pq non-router nodes
83only.
84.Pp
85If you invoke the program as
86.Nm rtsol ,
87it will transmit probes from the specified
88.Ar interface ,
89without becoming a daemon.
90In other words,
91.Nm rtsol
92behaves as
93.Do
94.Nm
95.Fl f1
96.Ar interfaces
97.Dc .
98.Pp
99Specifically,
100.Nm
101sends at most 3 Router Solicitations on an interface
102after one of the following events:
103.Pp
104.Bl -bullet -compact
105.It
106Just after invocation of
107.Nm
108daemon.
109.It
110The interface is up after a temporary interface failure.
111.Nm
112detects such failures by periodically probing to see if the status
113of the interface is active or not.
114Note that some network cards and drivers do not allow the extraction
115of link state.
116In such cases,
117.Nm
118cannot detect the change of the interface status.
119.It
120Every 60 seconds if the
121.Fl m
122option is specified and the
123.Nm
124daemon cannot get the interface status.
125This feature does not conform to the IPv6 neighbor discovery
126specification, but is provided for mobile stations.
127The default interval for router advertisements, which is on the order of 10
128minutes, is slightly long for mobile stations.
129This feature is provided
130for such stations so that they can find new routers as soon as possible
131when they attach to another link.
132.El
133.Lp
134Once
135.Nm
136has sent a Router Solicitation, and has received a valid Router Advertisement,
137it refrains from sending additional solicitations on that interface, until
138the next time one of the above events occurs.
139.Lp
140When sending a Router Solicitation on an interface,
141.Nm
142includes a Source Link-layer address option if the interface
143has a link-layer address.
144.Lp
145.Nm
146manages a per-interface parameter to detect if a separate protocol is
147needed for configuration parameters other than host's addresses.
148At the invocation time, the flag is FALSE, and becomes TRUE when
149the daemon receives a router advertisement with the OtherConfig flag
150being set.
151A script file can be specified to deal with the case
152.Pq see below .
153When
154.Nm
155start resending router solicitation messages by one of the conditions
156events,
157the daemon resets the parameter because the event may indicate a
158change on the attached link.
159.Pp
160Upon receipt of signal
161.Dv SIGUSR1 ,
162.Nm
163will dump the current internal state into
164.Pa /var/run/rtsold.dump .
165.\"
166.Pp
167The options are as follows:
168.Bl -tag -width indent
169.It Fl a
170Autoprobe outgoing interfaces.
171.Nm
172will try to find any non-loopback, IPv6-capable interfaces
173and send router solicitation messages on all of them.
174.It Fl d
175Enable debugging.
176.It Fl D
177Enable more debugging including the printing of internal timer information.
178.It Fl f
179Prevent
180.Nm
181from becoming a daemon (foreground mode).
182Warning messages are generated to standard error
183instead of
184.Xr syslog 3 .
185.It Fl F
186Explicitly configure the kernel to accept Router Advertisements and
187disable IPv6 forwarding.
188These settings are required for proper
189.Nm
190operation.
191Without this option, the current settings will be obeyed;
192if they are incompatible with proper operation,
193warning messages will be generated,
194but Router Solicitations will still be sent.
195The settings may be changed manually with
196.Xr sysctl 8
197and
198.Xr ifconfig 8 .
199.It Fl i
200Transmit Router Solicitation packets immediately, without waiting the
201normal random (between 0 and 1 second) delay.
202This option should not be used on networks where it might result in
203congestion due to many hosts simultaneously (re)connecting and
204sending such packets.
205.It Fl m
206Enable mobility support.
207If this option is specified,
208.Nm
209sends probing packets to default routers that have advertised Router
210Advertisements
211when the node (re)attaches to an interface.
212Moreover, if the option is specified,
213.Nm
214periodically sends Router Solicitation on an interface that does not support
215.Dv SIOCGIFMEDIA
216ioctl.
217.It Fl 1
218Perform only one probe.
219Transmit Router Solicitation packets until at least one valid Router
220Advertisement packet has arrived on each
221.Ar interface ,
222then exit.
223.It Fl M Ar script-name
224Specifies a supplement script file to handle the Managed Configuration
225flag of the router advertisement.
226When the flag changes from FALSE to TRUE,
227.Nm
228will invoke
229.Ar script-name
230with a first argument of the receiving interface name
231and a second argument of the sending router address,
232expecting the script will then start a protocol for the managed
233configuration.
234.Ar script-name
235must be the absolute path from root to the script file, be a regular
236file, and be created by the same owner who runs
237.Nm .
238.It Fl O Ar script-name
239Specifies a supplement script file to handle the Other Configuration
240flag of the router advertisement.
241When the flag changes from FALSE to TRUE,
242.Nm
243will invoke
244.Ar script-name
245with a first argument of the receiving interface name
246and a second argument of the sending router address,
247expecting the script will then start a protocol for the other
248configuration.
249The script will not be run if the Managed Configuration flag in the
250router advertisement is also TRUE.
251.Ar script-name
252must be the absolute path from root to the script file, be a regular
253file, and be created by the same owner who runs
254.Nm .
255.It Fl A Ar script-name
256Specifies a supplement script file to always be called for the router
257advertisement.
258.Nm
259will invoke
260.Ar script-name
261with a first argument of the receiving interface name
262and a second argument of the sending router address.
263.Ar script-name
264must be the absolute path from root to the script file, be a regular
265file, and be created by the same owner who runs
266.Nm .
267.It Fl p Ar pidfile
268Writes the process ID of
269.Nm
270to
271.Pa pidfile
272instead of the default PID file
273.Pa /var/run/rtsold.pid .
274.It Fl R Ar script-name
275Specifies a script to run when router advertisement options
276.Dv RDNSS Pq Recursive DNS Server
277or
278.Dv DNSSL Pq DNS Search List
279are encountered.
280The information of DNS servers and DNS search domains will be sent to
281standard input of this script.
282The
283.Xr resolvconf 8
284script is used by default.
285.It Fl u
286Specifies whether to add the source address of Router Advertisement
287messages to the interface name in the parameters of the RDNSS and DNSSL
288scripts.
289.Pp
290If
291.Fl u
292is specified, the interface name in the script parameters will be
293.Ql ifname:slaac:[RA-source-address] .
294.Pp
295Otherwise it will be
296.Ql ifname:slaac .
297.El
298.Sh FILES
299.Bl -tag -width /var/run/rtsold.dump -compact
300.It Pa /var/run/rtsold.pid
301The PID of the currently running
302.Nm .
303.It Pa /var/run/rtsold.dump
304Internal state dump file.
305.El
306.\"
307.Sh EXIT STATUS
308.Ex -std
309.\"
310.Sh SEE ALSO
311.Xr resolvconf 8 ,
312.Xr rtadvd 8 ,
313.Xr sysctl 8
314.\"
315.Sh HISTORY
316The
317.Nm
318command is based on the
319.Nm rtsol
320command, which first appeared in WIDE/KAME IPv6 protocol stack kit.
321.Nm rtsol
322is now integrated into
323.Xr rtsold 8 .
324.\"
325.Sh BUGS
326When a network card is removed and reinserted, the corresponding interface index
327may change.
328However,
329.Nm
330assumes such changes will not occur, and always uses the index that
331it got at invocation.
332As a result,
333.Nm
334may not work if you reinsert a network card.
335In such a case,
336.Nm
337should be killed and restarted.
338.Pp
339The IPv6 autoconfiguration specification assumes a single-interface host.
340You may see kernel error messages if you try to autoconfigure a host with
341multiple interfaces.
342Also, it seems contradictory for
343.Nm
344to accept multiple
345.Ar interface
346arguments.
347