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

[Mark Summerfield]

Ah, it seems like CNAME records don't conflict with A and AAAA.

But is it wise or unwise to have both?

:-)


On Fri, 8 Aug 2014 13:58:14 +0100
Mark Summerfield <mark at qtrac.eu> wrote:
> 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
        "Python in Practice" - ISBN 978-0321905635
            http://www.qtrac.eu/pipbook.html