[Swlug] DNS - do A & AAAA conflict with CNAME?

[Mark Summerfield]

Hi,

Do A and AAAA DNS records conflict with CNAME records or is it OK to
have both?

Case #1.

I have domain digitalcardbox.com and a website for it on Google App
Engine (GAE) at digitalcardbox.appspot.com

To make GAE use the digitalcardbox.com domain name I told GAE to verify
my ownership which it did and then added a TXT record:

    @ 3600 IN TXT "google-site-verification=XXXX"

It (or me, I can't recall which) then added two CNAME records:

    * 10800 IN CNAME ghs.googlehosted.com.
    www 10800 IN CNAME ghs.googlehosted.com.

And after a couple of days it seemed to work fine.

Case #2.

I also have domain qtrac.eu with the website hosted by plus.net.
And I have a GAE version of the website at diffpdf.appspot.com.

Around 4am this morning plus.net shut down qtrac.eu on the grounds that
there was too much traffic. They didn't say whether this was due to
popularity (which I doubt) or a DoS attack or simple extortion on their
part.

So, I tried to get GAE to take over the website.

First I reset the DNS back to gandi (from whom I get my domain names)
from plus.net and that worked OK.

Unfortunately GAE couldn't create the TXT record so I did that manually:

    @ 10800 IN TXT "google-site-verification=XXXX"

But unlike with digitalcardbox, GAE did not give me any CNAMEs to add,
so I added the two shown above.

GAE did ask me to add 4 A and 4 AAAA records (the A's look like IPv4 and
the AAAA a bit like IPv6 but I'm guessing), which I duly added.

My question is: will the CNAME records I added (and which GAE didn't ask
me to add) conflict with the A and AAAA records, or is it safe to have
them all?

If you get the impression I don't understand any of this you'd be right.

Thanks!

-- 
Mark Summerfield, Qtrac Ltd, www.qtrac.eu
    Python and PyQt/PySide - training and consultancy
        DiffPDF for Windows - PDF comparison tool
            http://www.qtrac.eu/diffpdf.html