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> User Guide: A Guide to Installing, Configuring, and Running <SPAN
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><TT
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><I
>servername</I
></TT
> Lookup</A
></H1
><P
><SPAN
CLASS="PRODUCTNAME"
>FreeTDS</SPAN
> converts the servername to an IP address by following the steps below, stopping when it succeeds.
			<P
></P
><P
><B
>Name lookup sequence
					<A
NAME="AEN914"
HREF="#FTN.AEN914"
><SPAN
CLASS="footnote"
>[1]</SPAN
></A
>
					</B
></P
><OL
TYPE="1"
><LI
><P
>Find <TT
CLASS="REPLACEABLE"
><I
>servername</I
></TT
> in <TT
CLASS="FILENAME"
>freetds.conf</TT
>.  If a section with that name exists, use the hostname, port, and TDS version specified therein.</P
></LI
><LI
><P
>Attempt to convert <TT
CLASS="REPLACEABLE"
><I
>servername</I
></TT
> to an IP address with <CODE
CLASS="FUNCTION"
>inet_addr(3)</CODE
>.</P
></LI
><LI
><P
>Request name-lookup from the operating system via <CODE
CLASS="FUNCTION"
>gethostbyname(3)</CODE
> or similar.</P
></LI
></OL
>
			
			If the TDS version and port are not read from <TT
CLASS="FILENAME"
>freetds.conf</TT
>, they are derived from the compiled-in defaults and overridden by applicable environment variables.</P
><P
>As you can see, if most of your servers use the same TDS version and answer to the default port, then you don't need to list them all in <TT
CLASS="FILENAME"
>freetds.conf</TT
>.  You can simply compile in the right defaults &mdash; or set the <CODE
CLASS="ENVAR"
>TDSPORT</CODE
> and <CODE
CLASS="ENVAR"
>TDSVER</CODE
> environment variables &mdash; and rely on DNS for name resolution.</P
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><H3
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>Notes</H3
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><SPAN
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>[1]</SPAN
></A
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><P
>This description applies to <SPAN
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>DB-Library</SPAN
> and <SPAN
CLASS="SYSTEMITEM"
>CT-Library</SPAN
>.  ODBC lookup is different.</P
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