Getting different IP's from same DNS server on different machines

[Barry Margolin]

In article <a2hr5j$obq at pub3.rc.vix.com>,
Brad White  <bwhite118 at homenospam.com> wrote:
>I am having a problem in which so far I have no explanation for.  I am
>having problems connecting to certain websites on a machine that has 
>Windows
>XP loaded.  When I hookup another system that has Windows ME loaded, I am
>able to access the previously inaccessible sites.  On each machine I did a
>DNS lookup of the URL's I couldn't access and got a different IP address 
>for
>each one.  For example www.microsoft.com comes back as 207.46.130.14 on the
>system that doesn't work right but as 207.46.197.102 on the machine that
>does. www.sportsline.com comes back as 206.79.229.17 on the bad and as
>216.34.40.200 on the good.  When I checked ipconfig /all on each they both
>show the same DNS servers.  Anyone have any ideas why I would be getting 
>two different IP addresses on two different computers hooked up to the same 
>connection?

www.microsoft.com has several addresses:

% dig www.microsoft.com a

; <<>> DiG 8.3 <<>> www.microsoft.com a 
;; res options: init recurs defnam dnsrch
;; got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 4
;; flags: qr rd ra; QUERY: 1, ANSWER: 8, AUTHORITY: 7, ADDITIONAL: 7
;; QUERY SECTION:
;;	www.microsoft.com, type = A, class = IN

;; ANSWER SECTION:
www.microsoft.com.	1h2m50s IN CNAME  www.microsoft.akadns.net.
www.microsoft.akadns.net.  5M IN A  207.46.197.113
www.microsoft.akadns.net.  5M IN A  207.46.197.100
www.microsoft.akadns.net.  5M IN A  207.46.197.101
www.microsoft.akadns.net.  5M IN A  207.46.230.220
www.microsoft.akadns.net.  5M IN A  207.46.197.102
www.microsoft.akadns.net.  5M IN A  207.46.230.218
www.microsoft.akadns.net.  5M IN A  207.46.230.219

Since this seems to be going through Akamai's server load-balancing system,
the addresses can probably change over time.  Many large web sites make use
of systems like this.

-- 
Barry Margolin, barmar at genuity.net
Genuity, Woburn, MA
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