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IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, 12 - INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 13 - LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE 14 - OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 15 - PERFORMANCE OF THIS SOFTWARE. 16--> 17<!-- Id --> 18<html> 19<head> 20<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> 21<title>dig</title> 22<meta name="generator" content="DocBook XSL Stylesheets V1.71.1"> 23</head> 24<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="refentry" lang="en"> 25<a name="man.dig"></a><div class="titlepage"></div> 26<div class="refnamediv"> 27<h2>Name</h2> 28<p>dig — DNS lookup utility</p> 29</div> 30<div class="refsynopsisdiv"> 31<h2>Synopsis</h2> 32<div class="cmdsynopsis"><p><code class="command">dig</code> [@server] [<code class="option">-b <em class="replaceable"><code>address</code></em></code>] [<code class="option">-c <em class="replaceable"><code>class</code></em></code>] [<code class="option">-f <em class="replaceable"><code>filename</code></em></code>] [<code class="option">-k <em class="replaceable"><code>filename</code></em></code>] [<code class="option">-m</code>] [<code class="option">-p <em class="replaceable"><code>port#</code></em></code>] [<code class="option">-q <em class="replaceable"><code>name</code></em></code>] [<code class="option">-t <em class="replaceable"><code>type</code></em></code>] [<code class="option">-v</code>] [<code class="option">-x <em class="replaceable"><code>addr</code></em></code>] [<code class="option">-y <em class="replaceable"><code>[<span class="optional">hmac:</span>]name:key</code></em></code>] [<code class="option">-4</code>] [<code class="option">-6</code>] [name] [type] [class] [queryopt...]</p></div> 33<div class="cmdsynopsis"><p><code class="command">dig</code> [<code class="option">-h</code>]</p></div> 34<div class="cmdsynopsis"><p><code class="command">dig</code> [global-queryopt...] [query...]</p></div> 35</div> 36<div class="refsect1" lang="en"> 37<a name="id2543544"></a><h2>DESCRIPTION</h2> 38<p><span><strong class="command">dig</strong></span> 39 (domain information groper) is a flexible tool 40 for interrogating DNS name servers. It performs DNS lookups and 41 displays the answers that are returned from the name server(s) that 42 were queried. Most DNS administrators use <span><strong class="command">dig</strong></span> to 43 troubleshoot DNS problems because of its flexibility, ease of use and 44 clarity of output. Other lookup tools tend to have less functionality 45 than <span><strong class="command">dig</strong></span>. 46 </p> 47<p> 48 Although <span><strong class="command">dig</strong></span> is normally used with 49 command-line 50 arguments, it also has a batch mode of operation for reading lookup 51 requests from a file. A brief summary of its command-line arguments 52 and options is printed when the <code class="option">-h</code> option is given. 53 Unlike earlier versions, the BIND 9 implementation of 54 <span><strong class="command">dig</strong></span> allows multiple lookups to be issued 55 from the 56 command line. 57 </p> 58<p> 59 Unless it is told to query a specific name server, 60 <span><strong class="command">dig</strong></span> will try each of the servers listed in 61 <code class="filename">/etc/resolv.conf</code>. If no usable server addresses 62 are found, <span><strong class="command">dig</strong></span> will send the query to the local 63 host. 64 </p> 65<p> 66 When no command line arguments or options are given, 67 <span><strong class="command">dig</strong></span> will perform an NS query for "." (the root). 68 </p> 69<p> 70 It is possible to set per-user defaults for <span><strong class="command">dig</strong></span> via 71 <code class="filename">${HOME}/.digrc</code>. This file is read and 72 any options in it 73 are applied before the command line arguments. 74 </p> 75<p> 76 The IN and CH class names overlap with the IN and CH top level 77 domain names. Either use the <code class="option">-t</code> and 78 <code class="option">-c</code> options to specify the type and class, 79 use the <code class="option">-q</code> the specify the domain name, or 80 use "IN." and "CH." when looking up these top level domains. 81 </p> 82</div> 83<div class="refsect1" lang="en"> 84<a name="id2543623"></a><h2>SIMPLE USAGE</h2> 85<p> 86 A typical invocation of <span><strong class="command">dig</strong></span> looks like: 87 </p> 88<pre class="programlisting"> dig @server name type </pre> 89<p> 90 where: 91 92 </p> 93<div class="variablelist"><dl> 94<dt><span class="term"><code class="constant">server</code></span></dt> 95<dd> 96<p> 97 is the name or IP address of the name server to query. This 98 can be an IPv4 address in dotted-decimal notation or an IPv6 99 address in colon-delimited notation. When the supplied 100 <em class="parameter"><code>server</code></em> argument is a hostname, 101 <span><strong class="command">dig</strong></span> resolves that name before querying 102 that name server. 103 </p> 104<p> 105 If no <em class="parameter"><code>server</code></em> argument is 106 provided, <span><strong class="command">dig</strong></span> consults 107 <code class="filename">/etc/resolv.conf</code>; if an 108 address is found there, it queries the name server at 109 that address. If either of the <code class="option">-4</code> or 110 <code class="option">-6</code> options are in use, then 111 only addresses for the corresponding transport 112 will be tried. If no usable addresses are found, 113 <span><strong class="command">dig</strong></span> will send the query to the 114 local host. The reply from the name server that 115 responds is displayed. 116 </p> 117</dd> 118<dt><span class="term"><code class="constant">name</code></span></dt> 119<dd><p> 120 is the name of the resource record that is to be looked up. 121 </p></dd> 122<dt><span class="term"><code class="constant">type</code></span></dt> 123<dd><p> 124 indicates what type of query is required — 125 ANY, A, MX, SIG, etc. 126 <em class="parameter"><code>type</code></em> can be any valid query 127 type. If no 128 <em class="parameter"><code>type</code></em> argument is supplied, 129 <span><strong class="command">dig</strong></span> will perform a lookup for an 130 A record. 131 </p></dd> 132</dl></div> 133<p> 134 </p> 135</div> 136<div class="refsect1" lang="en"> 137<a name="id2543726"></a><h2>OPTIONS</h2> 138<p> 139 The <code class="option">-b</code> option sets the source IP address of the query 140 to <em class="parameter"><code>address</code></em>. This must be a valid 141 address on 142 one of the host's network interfaces or "0.0.0.0" or "::". An optional 143 port 144 may be specified by appending "#<port>" 145 </p> 146<p> 147 The default query class (IN for internet) is overridden by the 148 <code class="option">-c</code> option. <em class="parameter"><code>class</code></em> is 149 any valid 150 class, such as HS for Hesiod records or CH for Chaosnet records. 151 </p> 152<p> 153 The <code class="option">-f</code> option makes <span><strong class="command">dig </strong></span> 154 operate 155 in batch mode by reading a list of lookup requests to process from the 156 file <em class="parameter"><code>filename</code></em>. The file contains a 157 number of 158 queries, one per line. Each entry in the file should be organized in 159 the same way they would be presented as queries to 160 <span><strong class="command">dig</strong></span> using the command-line interface. 161 </p> 162<p> 163 The <code class="option">-m</code> option enables memory usage debugging. 164 165 </p> 166<p> 167 If a non-standard port number is to be queried, the 168 <code class="option">-p</code> option is used. <em class="parameter"><code>port#</code></em> is 169 the port number that <span><strong class="command">dig</strong></span> will send its 170 queries 171 instead of the standard DNS port number 53. This option would be used 172 to test a name server that has been configured to listen for queries 173 on a non-standard port number. 174 </p> 175<p> 176 The <code class="option">-4</code> option forces <span><strong class="command">dig</strong></span> 177 to only 178 use IPv4 query transport. The <code class="option">-6</code> option forces 179 <span><strong class="command">dig</strong></span> to only use IPv6 query transport. 180 </p> 181<p> 182 The <code class="option">-t</code> option sets the query type to 183 <em class="parameter"><code>type</code></em>. It can be any valid query type 184 which is 185 supported in BIND 9. The default query type is "A", unless the 186 <code class="option">-x</code> option is supplied to indicate a reverse lookup. 187 A zone transfer can be requested by specifying a type of AXFR. When 188 an incremental zone transfer (IXFR) is required, 189 <em class="parameter"><code>type</code></em> is set to <code class="literal">ixfr=N</code>. 190 The incremental zone transfer will contain the changes made to the zone 191 since the serial number in the zone's SOA record was 192 <em class="parameter"><code>N</code></em>. 193 </p> 194<p> 195 The <code class="option">-q</code> option sets the query name to 196 <em class="parameter"><code>name</code></em>. This is useful to distinguish the 197 <em class="parameter"><code>name</code></em> from other arguments. 198 </p> 199<p> 200 The <code class="option">-v</code> causes <span><strong class="command">dig</strong></span> to 201 print the version number and exit. 202 </p> 203<p> 204 Reverse lookups — mapping addresses to names — are simplified by the 205 <code class="option">-x</code> option. <em class="parameter"><code>addr</code></em> is 206 an IPv4 207 address in dotted-decimal notation, or a colon-delimited IPv6 address. 208 When this option is used, there is no need to provide the 209 <em class="parameter"><code>name</code></em>, <em class="parameter"><code>class</code></em> and 210 <em class="parameter"><code>type</code></em> arguments. <span><strong class="command">dig</strong></span> 211 automatically performs a lookup for a name like 212 <code class="literal">11.12.13.10.in-addr.arpa</code> and sets the 213 query type and 214 class to PTR and IN respectively. By default, IPv6 addresses are 215 looked up using nibble format under the IP6.ARPA domain. 216 To use the older RFC1886 method using the IP6.INT domain 217 specify the <code class="option">-i</code> option. Bit string labels (RFC2874) 218 are now experimental and are not attempted. 219 </p> 220<p> 221 To sign the DNS queries sent by <span><strong class="command">dig</strong></span> and 222 their 223 responses using transaction signatures (TSIG), specify a TSIG key file 224 using the <code class="option">-k</code> option. You can also specify the TSIG 225 key itself on the command line using the <code class="option">-y</code> option; 226 <em class="parameter"><code>hmac</code></em> is the type of the TSIG, default HMAC-MD5, 227 <em class="parameter"><code>name</code></em> is the name of the TSIG key and 228 <em class="parameter"><code>key</code></em> is the actual key. The key is a 229 base-64 230 encoded string, typically generated by 231 <span class="citerefentry"><span class="refentrytitle">dnssec-keygen</span>(8)</span>. 232 233 Caution should be taken when using the <code class="option">-y</code> option on 234 multi-user systems as the key can be visible in the output from 235 <span class="citerefentry"><span class="refentrytitle">ps</span>(1)</span> 236 or in the shell's history file. When 237 using TSIG authentication with <span><strong class="command">dig</strong></span>, the name 238 server that is queried needs to know the key and algorithm that is 239 being used. In BIND, this is done by providing appropriate 240 <span><strong class="command">key</strong></span> and <span><strong class="command">server</strong></span> statements in 241 <code class="filename">named.conf</code>. 242 </p> 243</div> 244<div class="refsect1" lang="en"> 245<a name="id2544018"></a><h2>QUERY OPTIONS</h2> 246<p><span><strong class="command">dig</strong></span> 247 provides a number of query options which affect 248 the way in which lookups are made and the results displayed. Some of 249 these set or reset flag bits in the query header, some determine which 250 sections of the answer get printed, and others determine the timeout 251 and retry strategies. 252 </p> 253<p> 254 Each query option is identified by a keyword preceded by a plus sign 255 (<code class="literal">+</code>). Some keywords set or reset an 256 option. These may be preceded 257 by the string <code class="literal">no</code> to negate the meaning of 258 that keyword. Other 259 keywords assign values to options like the timeout interval. They 260 have the form <code class="option">+keyword=value</code>. 261 The query options are: 262 263 </p> 264<div class="variablelist"><dl> 265<dt><span class="term"><code class="option">+[no]aaflag</code></span></dt> 266<dd><p> 267 A synonym for <em class="parameter"><code>+[no]aaonly</code></em>. 268 </p></dd> 269<dt><span class="term"><code class="option">+[no]aaonly</code></span></dt> 270<dd><p> 271 Sets the "aa" flag in the query. 272 </p></dd> 273<dt><span class="term"><code class="option">+[no]additional</code></span></dt> 274<dd><p> 275 Display [do not display] the additional section of a 276 reply. The default is to display it. 277 </p></dd> 278<dt><span class="term"><code class="option">+[no]adflag</code></span></dt> 279<dd><p> 280 Set [do not set] the AD (authentic data) bit in the 281 query. This requests the server to return whether 282 all of the answer and authority sections have all 283 been validated as secure according to the security 284 policy of the server. AD=1 indicates that all records 285 have been validated as secure and the answer is not 286 from a OPT-OUT range. AD=0 indicate that some part 287 of the answer was insecure or not validated. This 288 bit is set by default. 289 </p></dd> 290<dt><span class="term"><code class="option">+[no]all</code></span></dt> 291<dd><p> 292 Set or clear all display flags. 293 </p></dd> 294<dt><span class="term"><code class="option">+[no]answer</code></span></dt> 295<dd><p> 296 Display [do not display] the answer section of a 297 reply. The default is to display it. 298 </p></dd> 299<dt><span class="term"><code class="option">+[no]authority</code></span></dt> 300<dd><p> 301 Display [do not display] the authority section of a 302 reply. The default is to display it. 303 </p></dd> 304<dt><span class="term"><code class="option">+[no]besteffort</code></span></dt> 305<dd><p> 306 Attempt to display the contents of messages which are 307 malformed. The default is to not display malformed 308 answers. 309 </p></dd> 310<dt><span class="term"><code class="option">+bufsize=B</code></span></dt> 311<dd><p> 312 Set the UDP message buffer size advertised using EDNS0 313 to <em class="parameter"><code>B</code></em> bytes. The maximum and 314 minimum sizes of this buffer are 65535 and 0 respectively. 315 Values outside this range are rounded up or down 316 appropriately. Values other than zero will cause a 317 EDNS query to be sent. 318 </p></dd> 319<dt><span class="term"><code class="option">+[no]cdflag</code></span></dt> 320<dd><p> 321 Set [do not set] the CD (checking disabled) bit in 322 the query. This requests the server to not perform 323 DNSSEC validation of responses. 324 </p></dd> 325<dt><span class="term"><code class="option">+[no]cl</code></span></dt> 326<dd><p> 327 Display [do not display] the CLASS when printing the 328 record. 329 </p></dd> 330<dt><span class="term"><code class="option">+[no]cmd</code></span></dt> 331<dd><p> 332 Toggles the printing of the initial comment in the 333 output identifying the version of <span><strong class="command">dig</strong></span> 334 and the query options that have been applied. This 335 comment is printed by default. 336 </p></dd> 337<dt><span class="term"><code class="option">+[no]comments</code></span></dt> 338<dd><p> 339 Toggle the display of comment lines in the output. 340 The default is to print comments. 341 </p></dd> 342<dt><span class="term"><code class="option">+[no]crypto</code></span></dt> 343<dd><p> 344 Toggle the display of cryptographic fields in DNSSEC 345 records. The contents of these field are unnecessary 346 to debug most DNSSEC validation failures and removing 347 them makes it easier to see the common failures. The 348 default is to display the fields. When omitted they 349 are replaced by the string "[omitted]" or in the 350 DNSKEY case the key id is displayed as the replacement, 351 e.g. "[ key id = value ]". 352 </p></dd> 353<dt><span class="term"><code class="option">+[no]defname</code></span></dt> 354<dd><p> 355 Deprecated, treated as a synonym for 356 <em class="parameter"><code>+[no]search</code></em> 357 </p></dd> 358<dt><span class="term"><code class="option">+[no]dnssec</code></span></dt> 359<dd><p> 360 Requests DNSSEC records be sent by setting the DNSSEC 361 OK bit (DO) in the OPT record in the additional section 362 of the query. 363 </p></dd> 364<dt><span class="term"><code class="option">+domain=somename</code></span></dt> 365<dd><p> 366 Set the search list to contain the single domain 367 <em class="parameter"><code>somename</code></em>, as if specified in 368 a <span><strong class="command">domain</strong></span> directive in 369 <code class="filename">/etc/resolv.conf</code>, and enable 370 search list processing as if the 371 <em class="parameter"><code>+search</code></em> option were given. 372 </p></dd> 373<dt><span class="term"><code class="option">+[no]edns[=#]</code></span></dt> 374<dd><p> 375 Specify the EDNS version to query with. Valid values 376 are 0 to 255. Setting the EDNS version will cause 377 a EDNS query to be sent. <code class="option">+noedns</code> 378 clears the remembered EDNS version. EDNS is set to 379 0 by default. 380 </p></dd> 381<dt><span class="term"><code class="option">+[no]expire</code></span></dt> 382<dd><p> 383 Send an EDNS Expire option. 384 </p></dd> 385<dt><span class="term"><code class="option">+[no]fail</code></span></dt> 386<dd><p> 387 Do not try the next server if you receive a SERVFAIL. 388 The default is to not try the next server which is 389 the reverse of normal stub resolver behavior. 390 </p></dd> 391<dt><span class="term"><code class="option">+[no]identify</code></span></dt> 392<dd><p> 393 Show [or do not show] the IP address and port number 394 that supplied the answer when the 395 <em class="parameter"><code>+short</code></em> option is enabled. If 396 short form answers are requested, the default is not 397 to show the source address and port number of the 398 server that provided the answer. 399 </p></dd> 400<dt><span class="term"><code class="option">+[no]ignore</code></span></dt> 401<dd><p> 402 Ignore truncation in UDP responses instead of retrying 403 with TCP. By default, TCP retries are performed. 404 </p></dd> 405<dt><span class="term"><code class="option">+[no]keepopen</code></span></dt> 406<dd><p> 407 Keep the TCP socket open between queries and reuse 408 it rather than creating a new TCP socket for each 409 lookup. The default is <code class="option">+nokeepopen</code>. 410 </p></dd> 411<dt><span class="term"><code class="option">+[no]multiline</code></span></dt> 412<dd><p> 413 Print records like the SOA records in a verbose 414 multi-line format with human-readable comments. The 415 default is to print each record on a single line, to 416 facilitate machine parsing of the <span><strong class="command">dig</strong></span> 417 output. 418 </p></dd> 419<dt><span class="term"><code class="option">+ndots=D</code></span></dt> 420<dd><p> 421 Set the number of dots that have to appear in 422 <em class="parameter"><code>name</code></em> to <em class="parameter"><code>D</code></em> 423 for it to be considered absolute. The default value 424 is that defined using the ndots statement in 425 <code class="filename">/etc/resolv.conf</code>, or 1 if no 426 ndots statement is present. Names with fewer dots 427 are interpreted as relative names and will be searched 428 for in the domains listed in the <code class="option">search</code> 429 or <code class="option">domain</code> directive in 430 <code class="filename">/etc/resolv.conf</code> if 431 <code class="option">+search</code> is set. 432 </p></dd> 433<dt><span class="term"><code class="option">+[no]nsid</code></span></dt> 434<dd><p> 435 Include an EDNS name server ID request when sending 436 a query. 437 </p></dd> 438<dt><span class="term"><code class="option">+[no]nssearch</code></span></dt> 439<dd><p> 440 When this option is set, <span><strong class="command">dig</strong></span> 441 attempts to find the authoritative name servers for 442 the zone containing the name being looked up and 443 display the SOA record that each name server has for 444 the zone. 445 </p></dd> 446<dt><span class="term"><code class="option">+[no]onesoa</code></span></dt> 447<dd><p> 448 Print only one (starting) SOA record when performing 449 an AXFR. The default is to print both the starting 450 and ending SOA records. 451 </p></dd> 452<dt><span class="term"><code class="option">+[no]qr</code></span></dt> 453<dd><p> 454 Print [do not print] the query as it is sent. By 455 default, the query is not printed. 456 </p></dd> 457<dt><span class="term"><code class="option">+[no]question</code></span></dt> 458<dd><p> 459 Print [do not print] the question section of a query 460 when an answer is returned. The default is to print 461 the question section as a comment. 462 </p></dd> 463<dt><span class="term"><code class="option">+[no]recurse</code></span></dt> 464<dd><p> 465 Toggle the setting of the RD (recursion desired) bit 466 in the query. This bit is set by default, which means 467 <span><strong class="command">dig</strong></span> normally sends recursive 468 queries. Recursion is automatically disabled when 469 the <em class="parameter"><code>+nssearch</code></em> or 470 <em class="parameter"><code>+trace</code></em> query options are used. 471 </p></dd> 472<dt><span class="term"><code class="option">+retry=T</code></span></dt> 473<dd><p> 474 Sets the number of times to retry UDP queries to 475 server to <em class="parameter"><code>T</code></em> instead of the 476 default, 2. Unlike <em class="parameter"><code>+tries</code></em>, 477 this does not include the initial query. 478 </p></dd> 479<dt><span class="term"><code class="option">+[no]rrcomments</code></span></dt> 480<dd><p> 481 Toggle the display of per-record comments in the 482 output (for example, human-readable key information 483 about DNSKEY records). The default is not to print 484 record comments unless multiline mode is active. 485 </p></dd> 486<dt><span class="term"><code class="option">+[no]search</code></span></dt> 487<dd> 488<p> 489 Use [do not use] the search list defined by the 490 searchlist or domain directive in 491 <code class="filename">resolv.conf</code> (if any). The search 492 list is not used by default. 493 </p> 494<p> 495 'ndots' from <code class="filename">resolv.conf</code> (default 1) 496 which may be overridden by <em class="parameter"><code>+ndots</code></em> 497 determines if the name will be treated as relative 498 or not and hence whether a search is eventually 499 performed or not. 500 </p> 501</dd> 502<dt><span class="term"><code class="option">+[no]short</code></span></dt> 503<dd><p> 504 Provide a terse answer. The default is to print the 505 answer in a verbose form. 506 </p></dd> 507<dt><span class="term"><code class="option">+[no]showsearch</code></span></dt> 508<dd><p> 509 Perform [do not perform] a search showing intermediate 510 results. 511 </p></dd> 512<dt><span class="term"><code class="option">+[no]sigchase</code></span></dt> 513<dd><p> 514 Chase DNSSEC signature chains. Requires dig be 515 compiled with -DDIG_SIGCHASE. 516 </p></dd> 517<dt><span class="term"><code class="option">+[no]sit[<span class="optional">=####</span>]</code></span></dt> 518<dd><p> 519 Send a Source Identity Token EDNS option, with optional 520 value. Replaying a SIT from a previous response will 521 allow the server to identify a previous client. The 522 default is <code class="option">+nosit</code>. Currently using 523 experimental value 65001 for the option code. 524 </p></dd> 525<dt><span class="term"><code class="option">+split=W</code></span></dt> 526<dd><p> 527 Split long hex- or base64-formatted fields in resource 528 records into chunks of <em class="parameter"><code>W</code></em> 529 characters (where <em class="parameter"><code>W</code></em> is rounded 530 up to the nearest multiple of 4). 531 <em class="parameter"><code>+nosplit</code></em> or 532 <em class="parameter"><code>+split=0</code></em> causes fields not to 533 be split at all. The default is 56 characters, or 534 44 characters when multiline mode is active. 535 </p></dd> 536<dt><span class="term"><code class="option">+[no]stats</code></span></dt> 537<dd><p> 538 This query option toggles the printing of statistics: 539 when the query was made, the size of the reply and 540 so on. The default behavior is to print the query 541 statistics. 542 </p></dd> 543<dt><span class="term"><code class="option">+[no]subnet=addr/prefix</code></span></dt> 544<dd><p> 545 Send an EDNS Client Subnet option with the specified 546 IP address or network prefix. 547 </p></dd> 548<dt><span class="term"><code class="option">+[no]tcp</code></span></dt> 549<dd><p> 550 Use [do not use] TCP when querying name servers. The 551 default behavior is to use UDP unless an 552 <code class="literal">ixfr=N</code> query is requested, in which 553 case the default is TCP. AXFR queries always use 554 TCP. 555 </p></dd> 556<dt><span class="term"><code class="option">+time=T</code></span></dt> 557<dd><p> 558 559 Sets the timeout for a query to 560 <em class="parameter"><code>T</code></em> seconds. The default 561 timeout is 5 seconds. 562 An attempt to set <em class="parameter"><code>T</code></em> to less 563 than 1 will result 564 in a query timeout of 1 second being applied. 565 </p></dd> 566<dt><span class="term"><code class="option">+[no]topdown</code></span></dt> 567<dd><p> 568 When chasing DNSSEC signature chains perform a top-down 569 validation. Requires dig be compiled with -DDIG_SIGCHASE. 570 </p></dd> 571<dt><span class="term"><code class="option">+[no]trace</code></span></dt> 572<dd> 573<p> 574 Toggle tracing of the delegation path from the root 575 name servers for the name being looked up. Tracing 576 is disabled by default. When tracing is enabled, 577 <span><strong class="command">dig</strong></span> makes iterative queries to 578 resolve the name being looked up. It will follow 579 referrals from the root servers, showing the answer 580 from each server that was used to resolve the lookup. 581 </p> 582<p> 583 <span><strong class="command">+dnssec</strong></span> is also set when +trace 584 is set to better emulate the default queries from a 585 nameserver. 586 </p> 587</dd> 588<dt><span class="term"><code class="option">+tries=T</code></span></dt> 589<dd><p> 590 Sets the number of times to try UDP queries to server 591 to <em class="parameter"><code>T</code></em> instead of the default, 592 3. If <em class="parameter"><code>T</code></em> is less than or equal 593 to zero, the number of tries is silently rounded up 594 to 1. 595 </p></dd> 596<dt><span class="term"><code class="option">+trusted-key=####</code></span></dt> 597<dd> 598<p> 599 Specifies a file containing trusted keys to be used 600 with <code class="option">+sigchase</code>. Each DNSKEY record 601 must be on its own line. 602 </p> 603<p> 604 If not specified, <span><strong class="command">dig</strong></span> will look 605 for <code class="filename">/etc/trusted-key.key</code> then 606 <code class="filename">trusted-key.key</code> in the current 607 directory. 608 </p> 609<p> 610 Requires dig be compiled with -DDIG_SIGCHASE. 611 </p> 612</dd> 613<dt><span class="term"><code class="option">+[no]ttlid</code></span></dt> 614<dd><p> 615 Display [do not display] the TTL when printing the 616 record. 617 </p></dd> 618<dt><span class="term"><code class="option">+[no]vc</code></span></dt> 619<dd><p> 620 Use [do not use] TCP when querying name servers. This 621 alternate syntax to <em class="parameter"><code>+[no]tcp</code></em> 622 is provided for backwards compatibility. The "vc" 623 stands for "virtual circuit". 624 </p></dd> 625</dl></div> 626<p> 627 628 </p> 629</div> 630<div class="refsect1" lang="en"> 631<a name="id2545243"></a><h2>MULTIPLE QUERIES</h2> 632<p> 633 The BIND 9 implementation of <span><strong class="command">dig </strong></span> 634 supports 635 specifying multiple queries on the command line (in addition to 636 supporting the <code class="option">-f</code> batch file option). Each of those 637 queries can be supplied with its own set of flags, options and query 638 options. 639 </p> 640<p> 641 In this case, each <em class="parameter"><code>query</code></em> argument 642 represent an 643 individual query in the command-line syntax described above. Each 644 consists of any of the standard options and flags, the name to be 645 looked up, an optional query type and class and any query options that 646 should be applied to that query. 647 </p> 648<p> 649 A global set of query options, which should be applied to all queries, 650 can also be supplied. These global query options must precede the 651 first tuple of name, class, type, options, flags, and query options 652 supplied on the command line. Any global query options (except 653 the <code class="option">+[no]cmd</code> option) can be 654 overridden by a query-specific set of query options. For example: 655 </p> 656<pre class="programlisting"> 657dig +qr www.isc.org any -x 127.0.0.1 isc.org ns +noqr 658</pre> 659<p> 660 shows how <span><strong class="command">dig</strong></span> could be used from the 661 command line 662 to make three lookups: an ANY query for <code class="literal">www.isc.org</code>, a 663 reverse lookup of 127.0.0.1 and a query for the NS records of 664 <code class="literal">isc.org</code>. 665 666 A global query option of <em class="parameter"><code>+qr</code></em> is 667 applied, so 668 that <span><strong class="command">dig</strong></span> shows the initial query it made 669 for each 670 lookup. The final query has a local query option of 671 <em class="parameter"><code>+noqr</code></em> which means that <span><strong class="command">dig</strong></span> 672 will not print the initial query when it looks up the NS records for 673 <code class="literal">isc.org</code>. 674 </p> 675</div> 676<div class="refsect1" lang="en"> 677<a name="id2545305"></a><h2>IDN SUPPORT</h2> 678<p> 679 If <span><strong class="command">dig</strong></span> has been built with IDN (internationalized 680 domain name) support, it can accept and display non-ASCII domain names. 681 <span><strong class="command">dig</strong></span> appropriately converts character encoding of 682 domain name before sending a request to DNS server or displaying a 683 reply from the server. 684 If you'd like to turn off the IDN support for some reason, defines 685 the <code class="envar">IDN_DISABLE</code> environment variable. 686 The IDN support is disabled if the variable is set when 687 <span><strong class="command">dig</strong></span> runs. 688 </p> 689</div> 690<div class="refsect1" lang="en"> 691<a name="id2545328"></a><h2>FILES</h2> 692<p><code class="filename">/etc/resolv.conf</code> 693 </p> 694<p><code class="filename">${HOME}/.digrc</code> 695 </p> 696</div> 697<div class="refsect1" lang="en"> 698<a name="id2545345"></a><h2>SEE ALSO</h2> 699<p><span class="citerefentry"><span class="refentrytitle">host</span>(1)</span>, 700 <span class="citerefentry"><span class="refentrytitle">named</span>(8)</span>, 701 <span class="citerefentry"><span class="refentrytitle">dnssec-keygen</span>(8)</span>, 702 <em class="citetitle">RFC1035</em>. 703 </p> 704</div> 705<div class="refsect1" lang="en"> 706<a name="id2545382"></a><h2>BUGS</h2> 707<p> 708 There are probably too many query options. 709 </p> 710</div> 711</div></body> 712</html> 713