73 lines
3.0 KiB
HTML
73 lines
3.0 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
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<!--Converted with LaTeX2HTML 96.1-c (Feb 29, 1996) by Nikos Drakos (nikos@cbl.leeds.ac.uk), CBLU, University of Leeds -->
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<HTML>
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<HEAD>
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<TITLE>Configuring Name Server Lookups-- resolv.conf</TITLE>
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</HEAD>
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<BODY LANG="EN">
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<A HREF="node1.html"><IMG WIDTH=65 HEIGHT=24 ALIGN=BOTTOM ALT="contents" SRC="contents_motif.gif"></A> <BR>
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<B> Next:</B> <A HREF="node85.html">Resolver Robustness</A>
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<B>Up:</B> <A HREF="node81.html">The Resolver Library</A>
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<B> Previous:</B> <A HREF="node83.html">Resolver Environment Variables</A>
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<BR> <P>
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<H2><A NAME="SECTION008130000">Configuring Name Server Lookups-- resolv.conf</A></H2>
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When configuring the resolver library to use the BIND name service for
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host lookups, you also have to tell it which name servers to use.
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There is a separate file for this, called resolv.conf.
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If this file does not exist or is empty, the resolver assumes the
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name server is on your local host.
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<P>
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If you run a name server on your local host, you have to set it up
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separately, as will be explained in the following section.
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If your are on a local network and have the opportunity to use an
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existing nameserver, this should always be preferred.
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<P>
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The most important option in resolv.conf is nameserver,
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which gives the IP-address of a name server to use. If you specify
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several name servers by giving the nameserver option several
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times, they are tried in the order given. You should therefore put the
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most reliable server first. Currently, up to three name servers are
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supported.
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<P>
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If no nameserver option is given, the resolver attempts
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to connect to the name server on the local host.
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<p>
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Two other options, domain and search deal with default
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domains that are tacked onto a hostname if BIND fails to resolve it
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with the first query. The search option specifies a list of
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domain names to be tried. The list items are separated by spaces
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or tabs.
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<P>
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If no search option is given, a default search list is constructed
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from the local domain name by using the domain name itself, plus all
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parent domains up to the root. The local domain name may be given using
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the domain statement; if none is given, the resolver obtains
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it through the getdomainname(2) system call.
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<P>
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If this sounds confusing to you, consider this sample resolv.conf
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file for the Virtual Brewery:
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<pre>
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# /etc/resolv.conf
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# Our domain
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domain vbrew.com
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#
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# We use vlager as central nameserver:
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nameserver 191.72.1.1
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</pre>
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When resolving the name vale, the resolver would look up
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vale, and failing this, vale.vbrew.com, and
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vale.com.
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<P>
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<HR><A HREF="node1.html"><IMG WIDTH=65 HEIGHT=24 ALIGN=BOTTOM ALT="contents" SRC="contents_motif.gif"></A> <BR>
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<B> Next:</B> <A HREF="node85.html">Resolver Robustness</A>
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<B>Up:</B> <A HREF="node81.html">The Resolver Library</A>
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<B> Previous:</B> <A HREF="node83.html">Resolver Environment Variables</A>
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<P><ADDRESS>
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<I>Andrew Anderson <BR>
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Thu Mar 7 23:22:06 EST 1996</I>
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</ADDRESS>
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</BODY>
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</HTML>
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