

Why dropping www can be a problem - lamnk
http://awesometrousers.posterous.com/why-dropping-www-can-be-a-problem

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pzxc
>>A second level domain cannot be a CNAME record (note: unless you are
authoritative for the TLD itself).

It is technically an RFC violation to do this, but that doesn't mean you can't
do it. My DNS provider allows it and I use this method for several domains.

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mechanical_fish
The problem with indulging RFC violations is that then you're married to
whatever configuration is currently working. The future is uncertain, and if
you someday run into a use case that breaks (several of which are mentioned in
this article), or want to switch DNS providers, you'll find yourself
constrained.

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jonhendry
I've always thought it should have just been "web.blah.com". Same # of
characters, one syllable.

~~~
holychiz
thanks for a good idea.

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br41n
plus stupid IE can't set a cookie on 2 letter domain ( ie.com for example),
had this problem recently :|

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gxti
The last two points are pretty weak. A CNAME results in an extra round trip to
the DNS server, even if it does reduce the packet size. What the author did
not explain is that some DNS servers can preemptively send the reply to the
CNAME target along with the result, avoiding that extra round trip. You can
see this for example with www.google.com. However, Google returns only one
CNAME (www.l.google.com.) and it does not seem to vary over time or location.
My sample size is admittedly quite small. On the other hand, one could just as
easily skip the CNAME altogether and return only as many A records as will fit
into a packet.

The GeoDNS section didn't even attempt to link the feature to the article's
subject. Presumably the complaint was that it is harder to delegate the 2LD to
GeoDNS, but Google manages to do this as well. When squeezing out every last
millisecond of latency, you could do worse than to imitate Google.

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epochwolf
This is why I have both singleforest.com and singleforest.net. I will be using
the .net domain for apis, cdn, and other stuff as I need it.

