1.\" $KAME: rtadvd.conf.5,v 1.50 2005/01/14 05:30:59 jinmei Exp $ 2.\" 3.\" Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the project nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.Dd June 4, 2011 31.Dt RTADVD.CONF 5 32.Os 33.Sh NAME 34.Nm rtadvd.conf 35.Nd config file for router advertisement daemon 36.Sh DESCRIPTION 37This file describes how the router advertisement packets must be constructed 38for each of the interfaces. 39.Pp 40As described in 41.Xr rtadvd 8 , 42you do not have to set this configuration file up at all, 43unless you need some special configurations. 44You may even omit the file as a whole. 45In such cases, the 46.Nm rtadvd 47daemon will automatically configure itself using default values 48specified in the specification. 49.Pp 50It obeys the famous 51.Xr termcap 5 52file format. 53Each line in the file describes a network interface. 54Fields are separated by a colon 55.Pq Sq \&: , 56and each field contains one capability description. 57Lines may be concatenated by the 58.Sq \e 59character. 60The comment marker is the 61.Sq \&# 62character. 63.Sh CAPABILITIES 64Capabilities describe the value to be filled into ICMPv6 router 65advertisement messages and to control 66.Xr rtadvd 8 67behavior. 68Therefore, you are encouraged to read IETF neighbor discovery documents 69if you would like to modify the sample configuration file. 70.Pp 71Note that almost all items have default values. 72If you omit an item, the default value of the item will be used. 73.Pp 74There are two items which control the interval of sending router advertisements. 75These items can be omitted, then 76.Nm rtadvd 77will use the default values. 78.Bl -tag -width indent 79.It Cm \&maxinterval 80(num) The maximum time allowed between sending unsolicited 81multicast router advertisements 82.Pq unit: seconds . 83The default value is 600. 84Its value must be no less than 4 seconds 85and no greater than 1800 seconds. 86.It Cm \&mininterval 87(num) The minimum time allowed between sending unsolicited multicast 88router advertisements 89.Pq unit: seconds . 90The default value is the one third of value of 91.Cm maxinterval . 92Its value must be no less than 3 seconds and no greater than .75 * 93the value of 94.Cm maxinterval . 95.El 96.Pp 97The following items are for ICMPv6 router advertisement message 98header. 99These items can be omitted, then 100.Nm rtadvd 101will use the default values. 102.Bl -tag -width indent 103.It Cm \&chlim 104(num) The value for Cur Hop Limit field. 105The default value is 64. 106.It Cm \&raflags 107(str or num) A 8-bit flags field in router advertisement message header. 108This field can be specified either as a case-sensitive string or as an 109integer. 110A string consists of characters each of which corresponds to a 111particular flag bit(s). 112An integer should be the logical OR of all enabled bits. 113Bit 7 114.Po 115.Li 'm' or 0x80 116.Pc 117means Managed address configuration flag bit, 118and Bit 6 119.Po 120.Li 'o' or 0x40 121.Pc 122means Other stateful configuration flag bit. 123Bit 4 124.Po 125.Li 0x10 126.Pc 127and Bit 3 128.Po 129.Li 0x08 130.Pc 131are used to encode router preference. 132Bits 01 133.Po 134or 'h' 135.Pc 136means high, 00 means medium, and 11 137.Po 138or 'l' 139.Pc 140means low. 141Bits 10 is reserved, and must not be specified. 142There is no character to specify the medium preference explicitly. 143The default value of the entire flag is 0 144.Po 145or a null string, 146.Pc 147which means no additional 148configuration methods, and the medium router preference. 149.It Cm \&rltime 150(num) Router lifetime field 151.Pq unit: seconds . 152The value must be either zero or between 153the value of 154.Cm maxinterval 155and 9000. 156When 157.Nm rtadvd 158runs on a host, this value must explicitly set 0 on all the 159advertising interfaces as described in 160.Xr rtadvd 8 . 161The default value is 1800. 162.It Cm \&rtime 163(num) Reachable time field 164.Pq unit: milliseconds . 165The default value is 0, which means unspecified by this router. 166.It Cm \&retrans 167(num) Retrans Timer field 168.Pq unit: milliseconds . 169The default value is 0, which means unspecified by this router. 170.El 171.Pp 172The following items are for ICMPv6 prefix information option, 173which will be attached to router advertisement header. 174These items can be omitted, then 175.Nm rtadvd 176will automatically get appropriate prefixes from the kernel's routing table, 177and advertise the prefixes with the default parameters. 178Keywords other than 179.Cm clockskew 180and 181.Cm noifprefix 182can be augmented with a number, like 183.Dq Li prefix2 , 184to specify multiple prefixes. 185.Bl -tag -width indent 186.It Cm \&noifprefix 187(bool) Specifies no prefix on the network interfaces will be advertised. 188By default 189.Nm rtadvd 190automatically gathers on-link prefixes from all of the network interfaces 191and advertise them. 192The 193.Cm noifprefix 194disables that behavior. 195If this is specified and no 196.Cm addr 197keyword is specified, no prefix information option will be included in the 198message. 199.It Cm \&clockskew 200(num) Time skew to adjust link propagation delays and clock skews 201between routers on the link 202.Pq unit: seconds . 203This value is used in consistency check for locally-configured and 204advertised prefix lifetimes, and has its meaning when the local router 205configures a prefix on the link with a lifetime that decrements in 206real time. 207If the value is 0, it means the consistency check will be skipped 208for such prefixes. 209The default value is 0. 210.It Cm \&prefixlen 211(num) Prefix length field. 212The default value is 64. 213.It Cm \&pinfoflags 214(str or num) A 8-bit flags field in prefix information option. 215This field can be specified either as a case-sensitive string or as an 216integer. 217A string consists of characters each of which corresponds to a 218particular flag bit(s). 219An integer should be the logical OR of all enabled bits. 220Bit 7 221.Po 222.Li 'l' or 0x80 223.Pc 224means On-link flag bit, 225and Bit 6 226.Po 227.Li 'a' or 0x40 228.Pc 229means Autonomous address-configuration flag bit. 230The default value is "la" or 0xc0, i.e., both bits are set. 231.It Cm \&addr 232(str) The address filled into Prefix field. 233Since 234.Dq \&: 235is used for 236.Xr termcap 5 237file format as well as IPv6 numeric address, the field MUST be quoted by 238doublequote character. 239.It Cm \&vltime 240(num) Valid lifetime field 241.Pq unit: seconds . 242The default value is 2592000 (30 days). 243.It Cm \&vltimedecr 244(bool) This item means the advertised valid lifetime will decrement 245in real time, which is disabled by default. 246.It Cm \&pltime 247(num) Preferred lifetime field 248.Pq unit: seconds . 249The default value is 604800 (7 days). 250.It Cm \&pltimedecr 251(bool) This item means the advertised preferred lifetime will decrement 252in real time, which is disabled by default. 253.El 254.Pp 255The following item is for ICMPv6 MTU option, 256which will be attached to router advertisement header. 257This item can be omitted, then 258.Nm rtadvd 259will use the default value. 260.Bl -tag -width indent 261.It Cm \&mtu 262(num or str) MTU (maximum transmission unit) field. 263If 0 is specified, it means that the option will not be included. 264The default value is 0. 265If the special string 266.Dq auto 267is specified for this item, MTU option will be included and its value 268will be set to the interface MTU automatically. 269.El 270.Pp 271The following item controls ICMPv6 source link-layer address option, 272which will be attached to router advertisement header. 273As noted above, you can just omit the item, then 274.Nm rtadvd 275will use the default value. 276.Bl -tag -width indent 277.It Cm \&nolladdr 278(bool) By default 279.Po 280if 281.Cm \&nolladdr 282is not specified 283.Pc , 284.Xr rtadvd 8 285will try to get link-layer address for the interface from the kernel, 286and attach that in source link-layer address option. 287If this capability exists, 288.Xr rtadvd 8 289will not attach source link-layer address option to 290router advertisement packets. 291.El 292.Pp 293The following item controls ICMPv6 home agent information option, 294which was defined with mobile IPv6 support. 295It will be attached to router advertisement header just like other options do. 296.Bl -tag -width indent 297.It Cm \&hapref 298(num) Specifies home agent preference. 299If set to non-zero, 300.Cm \&hatime 301must be present as well. 302.It Cm \&hatime 303(num) Specifies home agent lifetime. 304.El 305.Pp 306When mobile IPv6 support is turned on for 307.Xr rtadvd 8 , 308advertisement interval option will be attached to router advertisement 309packet, by configuring 310.Cm \&maxinterval 311explicitly. 312.Pp 313The following items are for ICMPv6 route information option, 314which will be attached to router advertisement header. 315These items are optional. 316Each items can be augmented with number, like 317.Dq Li rtplen2 , 318to specify multiple routes. 319.Bl -tag -width indent 320.It Cm \&rtprefix 321(str) The prefix filled into the Prefix field of route information option. 322Since 323.Dq \&: 324is used for 325.Xr termcap 5 326file format as well as IPv6 numeric address, the field MUST be quoted by 327doublequote character. 328.It Cm \&rtplen 329(num) Prefix length field in route information option. 330The default value is 64. 331.It Cm \&rtflags 332(str or num) A 8-bit flags field in route information option. 333Currently only the preference values are defined. 334The notation is same as that of the raflags field. 335Bit 4 336.Po 337.Li 0x10 338.Pc 339and 340Bit 3 341.Po 342.Li 0x08 343.Pc 344are used to encode the route preference for the route. 345The default value is 0x00, i.e., medium preference. 346.It Cm \&rtltime 347(num) route lifetime field in route information option. 348.Pq unit: seconds . 349Since the specification does not define the default value of this 350item, the value for this item should be specified by hand. 351However, 352.Nm rtadvd 353allows this item to be unspecified, and uses the router lifetime 354as the default value in such a case, just for compatibility with an 355old version of the program. 356.El 357.Pp 358In the above list, each keyword beginning with 359.Dq Li rt 360could be replaced with the one beginning with 361.Dq Li rtr 362for backward compatibility reason. 363For example, 364.Cm rtrplen 365is accepted instead of 366.Cm rtplen . 367However, keywords that start with 368.Dq Li rtr 369have basically been obsoleted, and should not be used any more. 370.Pp 371The following items are for ICMPv6 Recursive DNS Server Option and 372DNS Search List Option 373.Pq RFC 6106 , 374which will be attached to router advertisement header. 375These items are optional. 376.Bl -tag -width indent 377.It Cm \&rdnss 378(str) The IPv6 address of one or more recursive DNS servers. 379The argument must be inside double quotes. 380Multiple DNS servers can be specified in a comma-separated string. 381If different lifetimes are needed for different servers, 382separate entries can be given by using 383.Cm rdnss , 384.Cm rdnss0 , 385.Cm rdnss1 , 386.Cm rdnss2 ... 387options with corresponding 388.Cm rdnssltime , 389.Cm rdnssltime0 , 390.Cm rdnssltime1 , 391.Cm rdnssltime2 ... 392entries. 393Note that the maximum number of servers depends on the receiver side. 394See also 395.Xr resolver 5 396manual page for resolver implementation in 397.Fx . 398.It Cm \&rdnssltime 399The lifetime of the 400.Cm rdnss 401DNS server entries. 402The default value is 3/2 of the interval time. 403.It Cm \&dnssl 404(str) One or more domain names in a comma-separated string. 405These domain names will be used when making DNS queries on a 406non-fully-qualified domain name. 407If different lifetimes are needed for different domains, separate entries 408can be given by using 409.Cm dnssl , 410.Cm dnssl0 , 411.Cm dnssl1 , 412.Cm dnssl2 ... 413options with corresponding 414.Cm dnsslltime , 415.Cm dnsslltime0 , 416.Cm dnsslltime1 , 417.Cm dnsslltime2 ... 418entries. 419Note that the maximum number of names depends on the receiver side. 420See also 421.Xr resolver 5 422manual page for resolver implementation in 423.Fx . 424.It Cm \&dnsslltime 425The lifetime of the 426.Cm dnssl 427DNS search list entries. 428The default value is 3/2 of the interval time. 429.El 430.Pp 431The following items are for PREF64 discovery 432.Pq RFC 8781 , 433which will advertise the network's NAT64 prefix to clients. 434These items are optional. 435.Bl -tag -width indent 436.It Cm \&pref64 437(str) The prefix to advertise in the PREF64 option. 438.It Cm \&pref64len 439(num) The length of the PREF64 prefix. 440This must be 96, 64, 56, 48, 40, or 32. 441If not specified, the default is 96. 442.It Cm \&pref64lifetime 443(num) The prefix lifetime to advertise in the PREF64 option. 444This should be at least as long as the RA lifetime, but cannot be greater 445than 65528. 446If not specified, the default is the RA lifetime, or 65528, whichever is lower. 447.El 448.Pp 449You can also refer one line from another by using 450.Cm tc 451capability. 452See 453.Xr termcap 5 454for details on the capability. 455.Sh EXAMPLES 456As presented above, all of the advertised parameters have default values 457defined in specifications, and hence you usually do not have to set them 458by hand, unless you need special non-default values. 459It can cause interoperability problem if you use an ill-configured 460parameter. 461.Pp 462To override a configuration parameter, you can specify the parameter alone. 463With the following configuration, 464.Xr rtadvd 8 465overrides the router lifetime parameter for the 466.Li ne0 467interface. 468.Bd -literal -offset indent 469ne0:\\ 470 :rltime#0: 471.Ed 472.Pp 473The following example manually configures prefixes advertised from the 474.Li ef0 475interface. 476The configuration must be used with the 477.Fl s 478option to 479.Xr rtadvd 8 . 480.Bd -literal -offset indent 481ef0:\\ 482 :addr="2001:db8:ffff:1000::":prefixlen#64: 483.Ed 484.Pp 485The following example configures the 486.Li wlan0 487interface and adds two DNS servers and a DNS domain search options 488using the default option lifetime values. 489.Bd -literal -offset indent 490wlan0:\\ 491 :addr="2001:db8:ffff:1000::":prefixlen#64:\\ 492 :rdnss="2001:db8:ffff::10,2001:db8:ffff::2:43":\\ 493 :dnssl="example.com": 494.Ed 495.Pp 496The following example presents the default values in an explicit manner. 497The configuration is provided just for reference purposes; 498YOU DO NOT NEED TO HAVE IT AT ALL. 499.Bd -literal -offset indent 500default:\\ 501 :chlim#64:raflags#0:rltime#1800:rtime#0:retrans#0:\\ 502 :pinfoflags="la":vltime#2592000:pltime#604800:mtu#0: 503ef0:\\ 504 :addr="2001:db8:ffff:1000::":prefixlen#64:tc=default: 505.Ed 506.Sh SEE ALSO 507.Xr resolver 5 , 508.Xr termcap 5 , 509.Xr rtadvd 8 , 510.Xr rtsol 8 511.Rs 512.%A Thomas Narten 513.%A Erik Nordmark 514.%A W. A. Simpson 515.%A Hesham Soliman 516.%T Neighbor Discovery for IP version 6 (IPv6) 517.%R RFC 4861 518.Re 519.Rs 520.%A Thomas Narten 521.%A Erik Nordmark 522.%A W. A. Simpson 523.%T Neighbor Discovery for IP version 6 (IPv6) 524.%R RFC 2461 (obsoleted by RFC 4861) 525.Re 526.Rs 527.%A Richard Draves 528.%T Default Router Preferences and More-Specific Routes 529.%R draft-ietf-ipngwg-router-selection-xx.txt 530.Re 531.Rs 532.%A J. Jeong 533.%A S. Park 534.%A L. Beloeil 535.%A S. Madanapalli 536.%T IPv6 Router Advertisement Options for DNS Configuration 537.%R RFC 6106 538.Re 539.Sh HISTORY 540The 541.Xr rtadvd 8 542and the configuration file 543.Nm 544first appeared in WIDE Hydrangea IPv6 protocol stack kit. 545.\" .Sh BUGS 546.\" (to be written) 547