external/bsd/bind/dist/doc/arm/man.nsupdate.html

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  42 <div class="refentry" lang="en">
  43 <a name="man.nsupdate"></a><div class="titlepage"></div>
  44 <div class="refnamediv">
  45 <h2>Name</h2>
  46 <p><span class="application">nsupdate</span> &#8212; Dynamic DNS update utility</p>
  47 </div>
  48 <div class="refsynopsisdiv">
  49 <h2>Synopsis</h2>
  50 <div class="cmdsynopsis"><p><code class="command">nsupdate</code>  [<code class="option">-d</code>] [<code class="option">-D</code>] [[<code class="option">-g</code>] |  [<code class="option">-o</code>] |  [<code class="option">-l</code>] |  [<code class="option">-y <em class="replaceable"><code>[<span class="optional">hmac:</span>]keyname:secret</code></em></code>] |  [<code class="option">-k <em class="replaceable"><code>keyfile</code></em></code>]] [<code class="option">-t <em class="replaceable"><code>timeout</code></em></code>] [<code class="option">-u <em class="replaceable"><code>udptimeout</code></em></code>] [<code class="option">-r <em class="replaceable"><code>udpretries</code></em></code>] [<code class="option">-R <em class="replaceable"><code>randomdev</code></em></code>] [<code class="option">-v</code>] [<code class="option">-T</code>] [<code class="option">-P</code>] [<code class="option">-V</code>] [filename]</p></div>
  51 </div>
  52 <div class="refsect1" lang="en">
  53 <a name="id2653616"></a><h2>DESCRIPTION</h2>
  54 <p><span><strong class="command">nsupdate</strong></span>
  55       is used to submit Dynamic DNS Update requests as defined in RFC 2136
  56       to a name server.
  57       This allows resource records to be added or removed from a zone
  58       without manually editing the zone file.
  59       A single update request can contain requests to add or remove more than
  60       one
  61       resource record.
  62     </p>
  63 <p>
  64       Zones that are under dynamic control via
  65       <span><strong class="command">nsupdate</strong></span>
  66       or a DHCP server should not be edited by hand.
  67       Manual edits could
  68       conflict with dynamic updates and cause data to be lost.
  69     </p>
  70 <p>
  71       The resource records that are dynamically added or removed with
  72       <span><strong class="command">nsupdate</strong></span>
  73       have to be in the same zone.
  74       Requests are sent to the zone's master server.
  75       This is identified by the MNAME field of the zone's SOA record.
  76     </p>
  77 <p>
  78       The
  79       <code class="option">-d</code>
  80       option makes
  81       <span><strong class="command">nsupdate</strong></span>
  82       operate in debug mode.
  83       This provides tracing information about the update requests that are
  84       made and the replies received from the name server.
  85     </p>
  86 <p>
  87       The <code class="option">-D</code> option makes <span><strong class="command">nsupdate</strong></span>
  88       report additional debugging information to <code class="option">-d</code>.
  89     </p>
  90 <p>
  91       The <code class="option">-L</code> option with an integer argument of zero or
  92       higher sets the logging debug level.  If zero, logging is disabled.
  93     </p>
  94 <p>
  95       Transaction signatures can be used to authenticate the Dynamic
  96       DNS updates.  These use the TSIG resource record type described
  97       in RFC 2845 or the SIG(0) record described in RFC 2535 and
  98       RFC 2931 or GSS-TSIG as described in RFC 3645.  TSIG relies on
  99       a shared secret that should only be known to
 100       <span><strong class="command">nsupdate</strong></span> and the name server.  Currently,
 101       the only supported encryption algorithm for TSIG is HMAC-MD5,
 102       which is defined in RFC 2104.  Once other algorithms are
 103       defined for TSIG, applications will need to ensure they select
 104       the appropriate algorithm as well as the key when authenticating
 105       each other.  For instance, suitable <span class="type">key</span> and
 106       <span class="type">server</span> statements would be added to
 107       <code class="filename">/etc/named.conf</code> so that the name server
 108       can associate the appropriate secret key and algorithm with
 109       the IP address of the client application that will be using
 110       TSIG authentication.  SIG(0) uses public key cryptography.
 111       To use a SIG(0) key, the public key must be stored in a KEY
 112       record in a zone served by the name server.
 113       <span><strong class="command">nsupdate</strong></span> does not read
 114       <code class="filename">/etc/named.conf</code>.
 115     </p>
 116 <p>
 117       GSS-TSIG uses Kerberos credentials.  Standard GSS-TSIG mode
 118       is switched on with the <code class="option">-g</code> flag.  A
 119       non-standards-compliant variant of GSS-TSIG used by Windows
 120       2000 can be switched on with the <code class="option">-o</code> flag.
 121     </p>
 122 <p><span><strong class="command">nsupdate</strong></span>
 123       uses the <code class="option">-y</code> or <code class="option">-k</code> option
 124       to provide the shared secret needed to generate a TSIG record
 125       for authenticating Dynamic DNS update requests, default type
 126       HMAC-MD5.  These options are mutually exclusive.
 127     </p>
 128 <p>
 129       When the <code class="option">-y</code> option is used, a signature is
 130       generated from
 131       [<span class="optional"><em class="parameter"><code>hmac:</code></em></span>]<em class="parameter"><code>keyname:secret.</code></em>
 132       <em class="parameter"><code>keyname</code></em> is the name of the key, and
 133       <em class="parameter"><code>secret</code></em> is the base64 encoded shared secret.
 134       <em class="parameter"><code>hmac</code></em> is the name of the key algorithm;
 135       valid choices are <code class="literal">hmac-md5</code>,
 136       <code class="literal">hmac-sha1</code>, <code class="literal">hmac-sha224</code>,
 137       <code class="literal">hmac-sha256</code>, <code class="literal">hmac-sha384</code>, or
 138       <code class="literal">hmac-sha512</code>.  If <em class="parameter"><code>hmac</code></em>
 139       is not specified, the default is <code class="literal">hmac-md5</code>.
 140       NOTE: Use of the <code class="option">-y</code> option is discouraged because the
 141       shared secret is supplied as a command line argument in clear text.
 142       This may be visible in the output from
 143       <span class="citerefentry"><span class="refentrytitle">ps</span>(1)</span>
 144       or in a history file maintained by the user's shell.
 145     </p>
 146 <p>
 147       With the
 148       <code class="option">-k</code> option, <span><strong class="command">nsupdate</strong></span> reads
 149       the shared secret from the file <em class="parameter"><code>keyfile</code></em>.
 150       Keyfiles may be in two formats: a single file containing
 151       a <code class="filename">named.conf</code>-format <span><strong class="command">key</strong></span>
 152       statement, which may be generated automatically by
 153       <span><strong class="command">ddns-confgen</strong></span>, or a pair of files whose names are
 154       of the format <code class="filename">K{name}.+157.+{random}.key</code> and
 155       <code class="filename">K{name}.+157.+{random}.private</code>, which can be
 156       generated by <span><strong class="command">dnssec-keygen</strong></span>.
 157       The <code class="option">-k</code> may also be used to specify a SIG(0) key used
 158       to authenticate Dynamic DNS update requests.  In this case, the key
 159       specified is not an HMAC-MD5 key.
 160     </p>
 161 <p>
 162       <span><strong class="command">nsupdate</strong></span> can be run in a local-host only mode
 163       using the <code class="option">-l</code> flag.  This sets the server address to
 164       localhost (disabling the <span><strong class="command">server</strong></span> so that the server
 165       address cannot be overridden).  Connections to the local server will
 166       use a TSIG key found in <code class="filename">/var/run/named/session.key</code>,
 167       which is automatically generated by <span><strong class="command">named</strong></span> if any
 168       local master zone has set <span><strong class="command">update-policy</strong></span> to
 169       <span><strong class="command">local</strong></span>.  The location of this key file can be
 170       overridden with the <code class="option">-k</code> option.
 171     </p>
 172 <p>
 173       By default, <span><strong class="command">nsupdate</strong></span>
 174       uses UDP to send update requests to the name server unless they are too
 175       large to fit in a UDP request in which case TCP will be used.
 176       The
 177       <code class="option">-v</code>
 178       option makes
 179       <span><strong class="command">nsupdate</strong></span>
 180       use a TCP connection.
 181       This may be preferable when a batch of update requests is made.
 182     </p>
 183 <p>
 184       The <code class="option">-p</code> sets the default port number to use for
 185       connections to a name server.  The default is 53.
 186     </p>
 187 <p>
 188       The <code class="option">-t</code> option sets the maximum time an update request
 189       can
 190       take before it is aborted.  The default is 300 seconds.  Zero can be
 191       used
 192       to disable the timeout.
 193     </p>
 194 <p>
 195       The <code class="option">-u</code> option sets the UDP retry interval.  The default
 196       is
 197       3 seconds.  If zero, the interval will be computed from the timeout
 198       interval
 199       and number of UDP retries.
 200     </p>
 201 <p>
 202       The <code class="option">-r</code> option sets the number of UDP retries. The
 203       default is
 204       3.  If zero, only one update request will be made.
 205     </p>
 206 <p>
 207       The <code class="option">-R <em class="replaceable"><code>randomdev</code></em></code> option
 208       specifies a source of randomness.  If the operating system
 209       does not provide a <code class="filename">/dev/random</code> or
 210       equivalent device, the default source of randomness is keyboard
 211       input.  <code class="filename">randomdev</code> specifies the name of
 212       a character device or file containing random data to be used
 213       instead of the default.  The special value
 214       <code class="filename">keyboard</code> indicates that keyboard input
 215       should be used.  This option may be specified multiple times.
 216     </p>
 217 <p>
 218       Other types can be entered using "TYPEXXXXX" where "XXXXX" is the
 219       decimal value of the type with no leading zeros.  The rdata,
 220       if present, will be parsed using the UNKNOWN rdata format,
 221       (&lt;backslash&gt; &lt;hash&gt; &lt;space&gt; &lt;length&gt;
 222       &lt;space&gt; &lt;hexstring&gt;).
 223     </p>
 224 <p>
 225       The <code class="option">-T</code> and <code class="option">-P</code> options print out
 226       lists of non-meta types for which the type-specific presentation
 227       formats are known.  <code class="option">-T</code> prints out the list of
 228       IANA-assigned types.  <code class="option">-P</code> prints out the list of
 229       private types specific to <span><strong class="command">named</strong></span>.  These options
 230       may be combined.  <span><strong class="command">nsupdate</strong></span> will exit after the
 231       lists are printed.
 232     </p>
 233 <p>
 234       The -V option causes <span><strong class="command">nsupdate</strong></span> to print the
 235       version number and exit.
 236     </p>
 237 </div>
 238 <div class="refsect1" lang="en">
 239 <a name="id2657457"></a><h2>INPUT FORMAT</h2>
 240 <p><span><strong class="command">nsupdate</strong></span>
 241       reads input from
 242       <em class="parameter"><code>filename</code></em>
 243       or standard input.
 244       Each command is supplied on exactly one line of input.
 245       Some commands are for administrative purposes.
 246       The others are either update instructions or prerequisite checks on the
 247       contents of the zone.
 248       These checks set conditions that some name or set of
 249       resource records (RRset) either exists or is absent from the zone.
 250       These conditions must be met if the entire update request is to succeed.
 251       Updates will be rejected if the tests for the prerequisite conditions
 252       fail.
 253     </p>
 254 <p>
 255       Every update request consists of zero or more prerequisites
 256       and zero or more updates.
 257       This allows a suitably authenticated update request to proceed if some
 258       specified resource records are present or missing from the zone.
 259       A blank input line (or the <span><strong class="command">send</strong></span> command)
 260       causes the
 261       accumulated commands to be sent as one Dynamic DNS update request to the
 262       name server.
 263     </p>
 264 <p>
 265       The command formats and their meaning are as follows:
 266       </p>
 267 <div class="variablelist"><dl>
 268 <dt><span class="term">
 269               <span><strong class="command">server</strong></span>
 270                {servername}
 271                [port]
 272             </span></dt>
 273 <dd><p>
 274               Sends all dynamic update requests to the name server
 275               <em class="parameter"><code>servername</code></em>.
 276               When no server statement is provided,
 277               <span><strong class="command">nsupdate</strong></span>
 278               will send updates to the master server of the correct zone.
 279               The MNAME field of that zone's SOA record will identify the
 280               master
 281               server for that zone.
 282               <em class="parameter"><code>port</code></em>
 283               is the port number on
 284               <em class="parameter"><code>servername</code></em>
 285               where the dynamic update requests get sent.
 286               If no port number is specified, the default DNS port number of
 287               53 is
 288               used.
 289             </p></dd>
 290 <dt><span class="term">
 291               <span><strong class="command">local</strong></span>
 292                {address}
 293                [port]
 294             </span></dt>
 295 <dd><p>
 296               Sends all dynamic update requests using the local
 297               <em class="parameter"><code>address</code></em>.
 298
 299               When no local statement is provided,
 300               <span><strong class="command">nsupdate</strong></span>
 301               will send updates using an address and port chosen by the
 302               system.
 303               <em class="parameter"><code>port</code></em>
 304               can additionally be used to make requests come from a specific
 305               port.
 306               If no port number is specified, the system will assign one.
 307             </p></dd>
 308 <dt><span class="term">
 309               <span><strong class="command">zone</strong></span>
 310                {zonename}
 311             </span></dt>
 312 <dd><p>
 313               Specifies that all updates are to be made to the zone
 314               <em class="parameter"><code>zonename</code></em>.
 315               If no
 316               <em class="parameter"><code>zone</code></em>
 317               statement is provided,
 318               <span><strong class="command">nsupdate</strong></span>
 319               will attempt determine the correct zone to update based on the
 320               rest of the input.
 321             </p></dd>
 322 <dt><span class="term">
 323               <span><strong class="command">class</strong></span>
 324                {classname}
 325             </span></dt>
 326 <dd><p>
 327               Specify the default class.
 328               If no <em class="parameter"><code>class</code></em> is specified, the
 329               default class is
 330               <em class="parameter"><code>IN</code></em>.
 331             </p></dd>
 332 <dt><span class="term">
 333               <span><strong class="command">ttl</strong></span>
 334                {seconds}
 335             </span></dt>
 336 <dd><p>
 337               Specify the default time to live for records to be added.
 338               The value <em class="parameter"><code>none</code></em> will clear the default
 339               ttl.
 340             </p></dd>
 341 <dt><span class="term">
 342               <span><strong class="command">key</strong></span>
 343                [hmac:] {keyname}
 344                {secret}
 345             </span></dt>
 346 <dd><p>
 347               Specifies that all updates are to be TSIG-signed using the
 348               <em class="parameter"><code>keyname</code></em> <em class="parameter"><code>secret</code></em> pair.
 349               If <em class="parameter"><code>hmac</code></em> is specified, then it sets the
 350               signing algorithm in use; the default is
 351               <code class="literal">hmac-md5</code>.  The <span><strong class="command">key</strong></span>
 352               command overrides any key specified on the command line via
 353               <code class="option">-y</code> or <code class="option">-k</code>.
 354             </p></dd>
 355 <dt><span class="term">
 356             <span><strong class="command">gsstsig</strong></span>
 357           </span></dt>
 358 <dd><p>
 359               Use GSS-TSIG to sign the updated.  This is equivalent to
 360               specifying <code class="option">-g</code> on the commandline.
 361             </p></dd>
 362 <dt><span class="term">
 363             <span><strong class="command">oldgsstsig</strong></span>
 364           </span></dt>
 365 <dd><p>
 366               Use the Windows 2000 version of GSS-TSIG to sign the updated.
 367               This is equivalent to specifying <code class="option">-o</code> on the
 368               commandline.
 369             </p></dd>
 370 <dt><span class="term">
 371             <span><strong class="command">realm</strong></span>
 372              {[<span class="optional">realm_name</span>]}
 373           </span></dt>
 374 <dd><p>
 375               When using GSS-TSIG use <em class="parameter"><code>realm_name</code></em> rather
 376               than the default realm in <code class="filename">krb5.conf</code>.  If no
 377               realm is specified the saved realm is cleared.
 378             </p></dd>
 379 <dt><span class="term">
 380               <span><strong class="command">[<span class="optional">prereq</span>] nxdomain</strong></span>
 381                {domain-name}
 382             </span></dt>
 383 <dd><p>
 384               Requires that no resource record of any type exists with name
 385               <em class="parameter"><code>domain-name</code></em>.
 386             </p></dd>
 387 <dt><span class="term">
 388               <span><strong class="command">[<span class="optional">prereq</span>] yxdomain</strong></span>
 389                {domain-name}
 390             </span></dt>
 391 <dd><p>
 392               Requires that
 393               <em class="parameter"><code>domain-name</code></em>
 394               exists (has as at least one resource record, of any type).
 395             </p></dd>
 396 <dt><span class="term">
 397               <span><strong class="command">[<span class="optional">prereq</span>] nxrrset</strong></span>
 398                {domain-name}
 399                [class]
 400                {type}
 401             </span></dt>
 402 <dd><p>
 403               Requires that no resource record exists of the specified
 404               <em class="parameter"><code>type</code></em>,
 405               <em class="parameter"><code>class</code></em>
 406               and
 407               <em class="parameter"><code>domain-name</code></em>.
 408               If
 409               <em class="parameter"><code>class</code></em>
 410               is omitted, IN (internet) is assumed.
 411             </p></dd>
 412 <dt><span class="term">
 413               <span><strong class="command">[<span class="optional">prereq</span>] yxrrset</strong></span>
 414                {domain-name}
 415                [class]
 416                {type}
 417             </span></dt>
 418 <dd><p>
 419               This requires that a resource record of the specified
 420               <em class="parameter"><code>type</code></em>,
 421               <em class="parameter"><code>class</code></em>
 422               and
 423               <em class="parameter"><code>domain-name</code></em>
 424               must exist.
 425               If
 426               <em class="parameter"><code>class</code></em>
 427               is omitted, IN (internet) is assumed.
 428             </p></dd>
 429 <dt><span class="term">
 430               <span><strong class="command">[<span class="optional">prereq</span>] yxrrset</strong></span>
 431                {domain-name}
 432                [class]
 433                {type}
 434                {data...}
 435             </span></dt>
 436 <dd><p>
 437               The
 438               <em class="parameter"><code>data</code></em>
 439               from each set of prerequisites of this form
 440               sharing a common
 441               <em class="parameter"><code>type</code></em>,
 442               <em class="parameter"><code>class</code></em>,
 443               and
 444               <em class="parameter"><code>domain-name</code></em>
 445               are combined to form a set of RRs.  This set of RRs must
 446               exactly match the set of RRs existing in the zone at the
 447               given
 448               <em class="parameter"><code>type</code></em>,
 449               <em class="parameter"><code>class</code></em>,
 450               and
 451               <em class="parameter"><code>domain-name</code></em>.
 452               The
 453               <em class="parameter"><code>data</code></em>
 454               are written in the standard text representation of the resource
 455               record's
 456               RDATA.
 457             </p></dd>
 458 <dt><span class="term">
 459               <span><strong class="command">[<span class="optional">update</span>] del[<span class="optional">ete</span>]</strong></span>
 460                {domain-name}
 461                [ttl]
 462                [class]
 463                [type [data...]]
 464             </span></dt>
 465 <dd><p>
 466               Deletes any resource records named
 467               <em class="parameter"><code>domain-name</code></em>.
 468               If
 469               <em class="parameter"><code>type</code></em>
 470               and
 471               <em class="parameter"><code>data</code></em>
 472               is provided, only matching resource records will be removed.
 473               The internet class is assumed if
 474               <em class="parameter"><code>class</code></em>
 475               is not supplied.  The
 476               <em class="parameter"><code>ttl</code></em>
 477               is ignored, and is only allowed for compatibility.
 478             </p></dd>
 479 <dt><span class="term">
 480               <span><strong class="command">[<span class="optional">update</span>] add</strong></span>
 481                {domain-name}
 482                {ttl}
 483                [class]
 484                {type}
 485                {data...}
 486             </span></dt>
 487 <dd><p>
 488               Adds a new resource record with the specified
 489               <em class="parameter"><code>ttl</code></em>,
 490               <em class="parameter"><code>class</code></em>
 491               and
 492               <em class="parameter"><code>data</code></em>.
 493             </p></dd>
 494 <dt><span class="term">
 495               <span><strong class="command">show</strong></span>
 496             </span></dt>
 497 <dd><p>
 498               Displays the current message, containing all of the
 499               prerequisites and
 500               updates specified since the last send.
 501             </p></dd>
 502 <dt><span class="term">
 503               <span><strong class="command">send</strong></span>
 504             </span></dt>
 505 <dd><p>
 506               Sends the current message.  This is equivalent to entering a
 507               blank line.
 508             </p></dd>
 509 <dt><span class="term">
 510               <span><strong class="command">answer</strong></span>
 511             </span></dt>
 512 <dd><p>
 513               Displays the answer.
 514             </p></dd>
 515 <dt><span class="term">
 516               <span><strong class="command">debug</strong></span>
 517             </span></dt>
 518 <dd><p>
 519               Turn on debugging.
 520             </p></dd>
 521 <dt><span class="term">
 522               <span><strong class="command">version</strong></span>
 523             </span></dt>
 524 <dd><p>
 525               Print version number.
 526             </p></dd>
 527 <dt><span class="term">
 528               <span><strong class="command">help</strong></span>
 529             </span></dt>
 530 <dd><p>
 531               Print a list of commands.
 532             </p></dd>
 533 </dl></div>
 534 <p>
 535     </p>
 536 <p>
 537       Lines beginning with a semicolon are comments and are ignored.
 538     </p>
 539 </div>
 540 <div class="refsect1" lang="en">
 541 <a name="id2689776"></a><h2>EXAMPLES</h2>
 542 <p>
 543       The examples below show how
 544       <span><strong class="command">nsupdate</strong></span>
 545       could be used to insert and delete resource records from the
 546       <span class="type">example.com</span>
 547       zone.
 548       Notice that the input in each example contains a trailing blank line so
 549       that
 550       a group of commands are sent as one dynamic update request to the
 551       master name server for
 552       <span class="type">example.com</span>.
 553
 554       </p>
 555 <pre class="programlisting">
 556 # nsupdate
 557 &gt; update delete oldhost.example.com A
 558 &gt; update add newhost.example.com 86400 A 172.16.1.1
 559 &gt; send
 560 </pre>
 561 <p>
 562     </p>
 563 <p>
 564       Any A records for
 565       <span class="type">oldhost.example.com</span>
 566       are deleted.
 567       And an A record for
 568       <span class="type">newhost.example.com</span>
 569       with IP address 172.16.1.1 is added.
 570       The newly-added record has a 1 day TTL (86400 seconds).
 571       </p>
 572 <pre class="programlisting">
 573 # nsupdate
 574 &gt; prereq nxdomain nickname.example.com
 575 &gt; update add nickname.example.com 86400 CNAME somehost.example.com
 576 &gt; send
 577 </pre>
 578 <p>
 579     </p>
 580 <p>
 581       The prerequisite condition gets the name server to check that there
 582       are no resource records of any type for
 583       <span class="type">nickname.example.com</span>.
 584
 585       If there are, the update request fails.
 586       If this name does not exist, a CNAME for it is added.
 587       This ensures that when the CNAME is added, it cannot conflict with the
 588       long-standing rule in RFC 1034 that a name must not exist as any other
 589       record type if it exists as a CNAME.
 590       (The rule has been updated for DNSSEC in RFC 2535 to allow CNAMEs to have
 591       RRSIG, DNSKEY and NSEC records.)
 592     </p>
 593 </div>
 594 <div class="refsect1" lang="en">
 595 <a name="id2689826"></a><h2>FILES</h2>
 596 <div class="variablelist"><dl>
 597 <dt><span class="term"><code class="constant">/etc/resolv.conf</code></span></dt>
 598 <dd><p>
 599             used to identify default name server
 600           </p></dd>
 601 <dt><span class="term"><code class="constant">/var/run/named/session.key</code></span></dt>
 602 <dd><p>
 603             sets the default TSIG key for use in local-only mode
 604           </p></dd>
 605 <dt><span class="term"><code class="constant">K{name}.+157.+{random}.key</code></span></dt>
 606 <dd><p>
 607             base-64 encoding of HMAC-MD5 key created by
 608             <span class="citerefentry"><span class="refentrytitle">dnssec-keygen</span>(8)</span>.
 609           </p></dd>
 610 <dt><span class="term"><code class="constant">K{name}.+157.+{random}.private</code></span></dt>
 611 <dd><p>
 612             base-64 encoding of HMAC-MD5 key created by
 613             <span class="citerefentry"><span class="refentrytitle">dnssec-keygen</span>(8)</span>.
 614           </p></dd>
 615 </dl></div>
 616 </div>
 617 <div class="refsect1" lang="en">
 618 <a name="id2689909"></a><h2>SEE ALSO</h2>
 619 <p>
 620       <em class="citetitle">RFC 2136</em>,
 621       <em class="citetitle">RFC 3007</em>,
 622       <em class="citetitle">RFC 2104</em>,
 623       <em class="citetitle">RFC 2845</em>,
 624       <em class="citetitle">RFC 1034</em>,
 625       <em class="citetitle">RFC 2535</em>,
 626       <em class="citetitle">RFC 2931</em>,
 627       <span class="citerefentry"><span class="refentrytitle">named</span>(8)</span>,
 628       <span class="citerefentry"><span class="refentrytitle">ddns-confgen</span>(8)</span>,
 629       <span class="citerefentry"><span class="refentrytitle">dnssec-keygen</span>(8)</span>.
 630     </p>
 631 </div>
 632 <div class="refsect1" lang="en">
 633 <a name="id2689966"></a><h2>BUGS</h2>
 634 <p>
 635       The TSIG key is redundantly stored in two separate files.
 636       This is a consequence of nsupdate using the DST library
 637       for its cryptographic operations, and may change in future
 638       releases.
 639     </p>
 640 </div>
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