C/C++ version Load balancer DNS

John Wobus jw354 at cornell.edu
Fri Apr 10 15:58:15 UTC 2009

On Apr 3, 2009, at 7:31 PM, MSP wrote:
> This sollution which I am thinking is for some telecom application and
> not for web browsers.
> I  kown that TTL for my requirement should be ZERO, so that no cashing
> happens.
> Please tell why we can not use DNS sollution for this.

You can indeed use the DNS, but depending upon details, you could run
into problems.  As has been mentioned, ISPs could run nameservers that
impose a minimum TTL or even ignore it.  The client OS could do
the same.  The client app might do the same, or might look up the number
once and expect it to work for a long time.  Some simple tests would
answer the questions for the pieces under your control, but
if you need to serve clients across the Internet, you might be taking
your chances regarding the world's caching nameservers.

Also, depending upon specfics, it may be that you want to use a
short, non-zero TTL.


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