FreeTDS Development Group

["Reid, Roger L." <roger.reid AT dpw.com>]

It might matter to Apache, depending on the change you made.   

I use DNS names to hide the server on a per application basis.  So db-appthis 
may point to 'sql001.etc' and db-appthat may point to 
'sql001.etc' as well.

Apache, in the name of security, blows this off by caching anything it has 
already resolved once (to prevent spoof attacks).  It ignores DNS changes for 
CNAMEs it has already resolved once.

I'm trying to think this through, as to whether a change in freetds.conf that 
does NOT involve a change in DNS could be a problem.

Where I have issues is when a developer has 'db-appthat' in thier web 
datasource, and I change DNS out from under them - so 
they are still looking for 'db-appthat', but it resolves now to 'sql002' 
(truly a different instance).  When I do that, Apache says, "I already know 
that 'db-appthat' is XXX.XXX.XXX.XXX" and will not re-resolve it and learn it 
is actually XXX.XXX.ZZZ.YYY now.  

I admit this is a special case, and strictly speaking violates the standards 
for CNAME - but it sure is flexible - has serve me well for connecting via 
various methods from Unix and Windows to Sybase on Unix and SQL Server on 
Windows.  

Except when it comes to Apache.  Anyway, I'm not sure this is at all relevant 
to more normal use, and how your developers make thier connections

roger reid


-----Original Message-----
From: James K. Lowden [mailto:jklowden AT freetds.org] 
Sent: Friday, April 06, 2007 3:29 PM
To: FreeTDS Development Group
Subject: Re: [freetds] freetds.conf

vadakkan wrote:
> Does apache, freetds or server need to be restarted after modifying
> freetds.conf  file?

freetds.conf is read each time a connection is made.  There's no way for
FreeTDS or apache to cache it anywhere.  

--jkl