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diff --git a/static/freebsd/man5/resolver.5 3.html b/static/freebsd/man5/resolver.5 3.html new file mode 100644 index 00000000..3f32c857 --- /dev/null +++ b/static/freebsd/man5/resolver.5 3.html @@ -0,0 +1,218 @@ +<table class="head"> + <tr> + <td class="head-ltitle">RESOLVER(5)</td> + <td class="head-vol">File Formats Manual</td> + <td class="head-rtitle">RESOLVER(5)</td> + </tr> +</table> +<div class="manual-text"> +<section class="Sh"> +<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> +<p class="Pp"><code class="Nm">resolver</code> — + <span class="Nd">resolver configuration file</span></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> +<table class="Nm"> + <tr> + <td><code class="Nm">resolv.conf</code></td> + <td></td> + </tr> +</table> +</section> +<section class="Sh"> +<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> +<p class="Pp">The <a class="Xr">resolver(3)</a> is a set of routines in the C + library which provide access to the Internet Domain Name System. The + resolver configuration file contains information that is read by the + resolver routines the first time they are invoked by a process. The file is + designed to be human readable and contains a list of keywords with values + that provide various types of resolver information.</p> +<p class="Pp">On a normally configured system, setting this file manually should + not be necessary. The only name server(s) to be queried will be on the local + machine or automatically configured using DHCP or a similar mechanism, the + domain name is determined from the host name, and the domain search path is + constructed from the domain name.</p> +<p class="Pp">The different configuration options are:</p> +<dl class="Bl-tag"> + <dt id="nameserver"><a class="permalink" href="#nameserver"><b class="Sy">nameserver</b></a></dt> + <dd>IPv4 or IPv6 address of a name server that the resolver should query. Up + to <code class="Dv">MAXNS</code> (currently 3) name servers may be listed, + one per keyword. If there are multiple servers, the resolver library + queries them in the order listed. If no <b class="Sy">nameserver</b> + entries are present, the default is to use the name server on the local + machine. (The algorithm used is to try a name server, and if the query + times out, try the next, until out of name servers, then repeat trying all + the name servers until a maximum number of retries are made).</dd> + <dt id="domain"><a class="permalink" href="#domain"><b class="Sy">domain</b></a></dt> + <dd>Local domain name. Most queries for names within this domain can use short + names relative to the local domain. If no <b class="Sy">domain</b> entry + is present, the domain is determined from the local host name returned by + <a class="Xr">gethostname(3)</a>; the domain part is taken to be + everything after the first ‘<code class="Li">.</code>’. + Finally, if the host name does not contain a domain part, the root domain + is assumed.</dd> + <dt id="search"><a class="permalink" href="#search"><b class="Sy">search</b></a></dt> + <dd>Search list for host-name lookup. The search list is normally determined + from the local domain name; by default, it contains only the local domain + name. This may be changed by listing the desired domain search path + following the <b class="Sy">search</b> keyword with spaces or tabs + separating the names. Most resolver queries will be attempted using each + component of the search path in turn until a match is found. Note that + this process may be slow and will generate a lot of network traffic if the + servers for the listed domains are not local, and that queries will time + out if no server is available for one of the domains. + <p class="Pp">The search list is currently limited to six domains with a + total of 256 characters.</p> + </dd> + <dt id="sortlist"><a class="permalink" href="#sortlist"><b class="Sy">sortlist</b></a></dt> + <dd>Sortlist allows addresses returned by gethostbyname to be sorted. A + sortlist is specified by IP address netmask pairs. If the netmask is not + specified, it defaults to the historical Class A/B/C netmask of the net; + this usage is deprecated. The IP address and network pairs are separated + by slashes. Up to 10 pairs may be specified. E.g., + <p class="Pp"></p> + <div class="Bd Bd-indent"><code class="Li">sortlist 10.9.1.0/255.255.240.0 + 10.9.0.0/255.255.0.0</code></div> + </dd> + <dt id="options"><a class="permalink" href="#options"><b class="Sy">options</b></a></dt> + <dd>Options allows certain internal resolver variables to be modified. The + syntax is + <p class="Pp"><b>options</b> <i>option</i> <i>...</i></p> + <p class="Pp" id="option">where + <a class="permalink" href="#option"><b class="Sy">option</b></a> is one + of the following:</p> + <dl class="Bl-tag"> + <dt id="debug"><a class="permalink" href="#debug"><b class="Sy">debug</b></a></dt> + <dd>sets <code class="Dv">RES_DEBUG</code> in _res.options.</dd> + <dt id="usevc"><a class="permalink" href="#usevc"><b class="Sy">usevc</b></a></dt> + <dd>sets <code class="Dv">RES_USEVC</code> to use TCP instead of UDP for + queries.</dd> + <dt id="ndots"><a class="permalink" href="#ndots"><b class="Sy">ndots</b></a>:<var class="Ar">n</var></dt> + <dd>sets a threshold for the number of dots which must appear in a name + given to + <a class="permalink" href="#res_query"><code class="Fn" id="res_query">res_query</code></a>() + (see <a class="Xr">resolver(3)</a>) before an + <a class="permalink" href="#initial"><i class="Em" id="initial">initial + absolute query</i></a> will be made. The default for + <a class="permalink" href="#n"><i class="Em" id="n">n</i></a> is + “1”, meaning that if there are any dots in a name, the + name will be tried first as an absolute name before any + <i class="Em">search list</i> elements are appended to it.</dd> + <dt id="timeout"><a class="permalink" href="#timeout"><b class="Sy">timeout</b></a>:<var class="Ar">n</var></dt> + <dd>sets the initial amount of time the resolver will wait for a response + from a remote name server before retrying the query via a different + name server. The resolver may wait longer during subsequent retries of + the current query since an exponential back-off is applied to the + timeout value. Measured in seconds, the default is + <code class="Dv">RES_TIMEOUT</code>, the allowed maximum is + <code class="Dv">RES_MAXRETRANS</code> (see + <code class="In"><<a class="In">resolv.h</a>></code>).</dd> + <dt id="attempts"><a class="permalink" href="#attempts"><b class="Sy">attempts</b></a>:<var class="Ar">n</var></dt> + <dd>sets the number of times the resolver will send a query to each of its + name servers before giving up and returning an error to the calling + application. The default is <code class="Dv">RES_DFLRETRY</code>, the + allowed maximum is <code class="Dv">RES_MAXRETRY</code> (see + <code class="In"><<a class="In">resolv.h</a>></code>).</dd> + <dt id="edns0"><a class="permalink" href="#edns0"><b class="Sy">edns0</b></a></dt> + <dd>Sets <code class="Dv">RES_USE_EDNS0</code>. Attach an OPT pseudo-RR + for the EDNS0 extension, as specified in RFC 2671. This allows the + resolver to advertise a larger UDP receive buffer size, permitting + responses larger than the original 512-byte limit.</dd> + <dt id="inet6"><a class="permalink" href="#inet6"><b class="Sy">inet6</b></a></dt> + <dd>Sets <code class="Dv">RES_USE_INET6</code>. Causes + <a class="Xr">gethostbyname(3)</a> to look up AAAA records before A + records and to map IPv4 responses into IPv6 addresses. The use of this + option is discouraged.</dd> + <dt id="insecure1"><a class="permalink" href="#insecure1"><b class="Sy">insecure1</b></a></dt> + <dd>Sets <code class="Dv">RES_INSECURE1</code>. Disables the check that + the response was received from the same server to which the query was + sent. Use of this option is a security risk and is not + recommended.</dd> + <dt id="insecure2"><a class="permalink" href="#insecure2"><b class="Sy">insecure2</b></a></dt> + <dd>Sets <code class="Dv">RES_INSECURE2</code>. Disables the check that + the response contains a query matching the one that was sent. Use of + this option is a security risk and is not recommended.</dd> + <dt id="no-check-names"><a class="permalink" href="#no-check-names"><b class="Sy">no-check-names</b></a></dt> + <dd>Sets <code class="Dv">RES_NOCHECKNAME</code>. Disables the check of + incoming host names for invalid characters such as underscore, + non-ASCII, or control characters.</dd> + <dt id="no_tld_query"><a class="permalink" href="#no_tld_query"><b class="Sy">no_tld_query</b></a></dt> + <dd>tells the resolver not to attempt to resolve a top level domain name, + that is, a name that contains no dots. Use of this option does not + prevent the resolver from obeying the standard + <b class="Sy">domain</b> and <b class="Sy">search</b> rules with the + given name.</dd> + <dt id="rotate"><a class="permalink" href="#rotate"><b class="Sy">rotate</b></a></dt> + <dd>Sets <code class="Dv">RES_ROTATE</code>. Causes the resolver to + round-robin among the configured name servers, distributing the query + load instead of always trying the first listed server.</dd> + <dt id="reload-period"><a class="permalink" href="#reload-period"><b class="Sy">reload-period</b></a>:<var class="Ar">n</var></dt> + <dd>The resolver checks the modification time of + <span class="Pa">/etc/resolv.conf</span> every <var class="Ar">n</var> + seconds. If <span class="Pa">/etc/resolv.conf</span> has changed, it + is automatically reloaded. The default for <var class="Ar">n</var> is + two seconds. Setting it to zero disables the file check.</dd> + </dl> + <p class="Pp">Options may also be specified as a space or tab separated list + using the <code class="Dv">RES_OPTIONS</code> environment variable.</p> + </dd> +</dl> +<p class="Pp">The <b class="Sy">domain</b> and <b class="Sy">search</b> keywords + are mutually exclusive. If more than one instance of these keywords is + present, the last instance will override.</p> +<p class="Pp">The keyword and value must appear on a single line, and the + keyword (for example, <b class="Sy">nameserver</b>) must start the line. The + value follows the keyword, separated by white space.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="FILES"><a class="permalink" href="#FILES">FILES</a></h1> +<dl class="Bl-tag Bl-compact"> + <dt><span class="Pa">/etc/resolv.conf</span></dt> + <dd>The file <code class="Nm">resolv.conf</code> resides in + <span class="Pa">/etc</span>.</dd> +</dl> +</section> +<section class="Sh"> +<h1 class="Sh" id="EXAMPLES"><a class="permalink" href="#EXAMPLES">EXAMPLES</a></h1> +<p class="Pp">A basic resolv.conf file could be in the following form.</p> +<div class="Bd Pp Bd-indent Li"> +<pre># The domain directive is only necessary, if your local +# router advertises something like localdomain and you have +# set up your hostnames via an external domain. +domain localdomain.tld + +# In case you a running a local dns server or caching name server +# like local-unbound(8) for example. +nameserver 127.0.0.1 + +# IP address of the local or ISP name service +nameserver 192.168.2.1 + +# Fallback nameservers, in this case these from Google. +nameserver 8.8.8.8 +nameserver 8.8.4.4 + +# Attach an OPT pseudo-RR for the EDNS0 extension, +# as specified in RFC 2671. +options edns0</pre> +</div> +</section> +<section class="Sh"> +<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE + ALSO</a></h1> +<p class="Pp"><a class="Xr">gethostbyname(3)</a>, <a class="Xr">resolver(3)</a>, + <a class="Xr">hostname(7)</a>, <a class="Xr">resolvconf(8)</a></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> +<p class="Pp">The <code class="Nm">resolv.conf</code> file format appeared in + <span class="Ux">4.3BSD</span>.</p> +</section> +</div> +<table class="foot"> + <tr> + <td class="foot-date">March 15, 2026</td> + <td class="foot-os">FreeBSD 15.0</td> + </tr> +</table> |