Ask HN: reasons for www. subdomain

[riobard]

I purchased a domain for personal use with Google App Engine, and I found it is not possible to link an app to the so-called naked domain (without any subdomain) now. This leads me wonder what is the technique reason behind this. From usability point of view I would really like to use a naked domain primarily, with www. redirects to the naked one. Is there any technique problem with this that Google does not allow me to do so?

[gojomo]

There is no inherent technical reason why you couldn't. And this article at Google (expand the first [+] area) suggests you can use non-www domains just fine:

http://www.google.com/support/a/bin/answer.py?hl=en&answ...

Where did you get the idea you couldn't?

(The only trick might be something specific to App Engine for generating the www -> non-www redirects, as you won't have the usual access to web server configuration options. But that'd be a better question for the App Engine forums.)

[noodle → gojomo]

i imagine because google says you can't.

http://code.google.com/appengine/kb/commontasks.html

"Due to recent changes, App Engine no longer supports mapping your app to a naked domain. If your domain registrar supports URL redirects, you can redirect from http://yourdomain.com to e.g http://www.yourdomain.com or http://appid.yourdomain.com."

[gojomo → noodle]

Aha. Guess I should have searched past finding a Google document saying it was possible!

Riobard should join the other AppEngine users pushing Google to restore this previously-available functionality, at this open AppEngine issue:

http://code.google.com/p/googleappengine/issues/detail?id=77...

Viewing the comments there, AppEngine users have had their inlinks and search rankings ruined by this change. So chalk this up as another reason to be wary of building in the Google-controlled cloud.

[riobard → gojomo]

Thanks for the suggestion! Since I just start to build the site, I am not affected by the linking and ranking stuff.

However I am interested in the following paragraph from the link you provided:

"From a GAE google groups post (posted by Google):

One question that we see a lot on the group is about setting up an app to serve from a naked domain (http://example.com) While this has been difficult but not impossible in the past, we've made some changes and are no longer allowing naked domains to be used for App Engine apps. The infrastructure which we use will occasionally force TCP connection resets when an app is running on a naked domain, so we're recommending that everyone switch to a subdomain (like http://www.example.com) and set up DNS redirects if you already have traffic going to a naked domain. "

I don't understand why using a naked domain lead to TCP connection resets. Is it a general case (which means using naked domain is a bad idea anyway), or is it just Google's problem?

Personally I think prefixing every domain with "www." is really a silly idea, but it seems now there is some technique difficulty behind it. Puzzled ...

[gojomo → riobard]

It must be a bug in their back-end infrastructure; there's no general reason why 'naked' domains should be any more prone to TCP connection problems than any other domains. (TCP doesn't even care about domain names, and even in DNS, 'naked' 2nd-level domains are functionally equivalent to 3rd-level domains, 4th-level domains, etc.).

There is at least one legitimate reason using www (or any other subdomain) can be beneficial -- to isolate application cookies from your base domain, to assist caching. See here for details:

http://developer.yahoo.com/performance/rules.html#cookie_fre...

However, you're probably far from needing to worry about that, and also segregating your static, highly-cacheable data to another domain is another way to get the same benefit.

(I tend to prefer non-www domains, too.)

[riobard → gojomo]

Thanks for the info!

I think the cookie/cache reason explained why virtually all major websites (millions hits/day) redirect naked domain to "www." subdomain.

I also found the following info from here http://blog.bigcurl.de/2008/08/redirect-naked-domains-to-sub...

"That is why I wrote redirector. It is a little application which redirects all the apps in your Google Apps account from a naked domain name to a subdomain.

Eg. bigcurl.de --> www.bigcurl.de

If you want it can also do this vice versa but be aware that you are not taking advantage of Googles geocaching mechanism with this approach."

So using "www." domain for GAE seems to be a better solution if one wants faster access/response.