how did Google Analytics kill my site?

Question

Yesterday I created a google analytics profile for one of my sites and included the JS block in the layout template. What happened next was very strange. Within about 2 minutes, the site had become unreachable.

I had been checking the AWStats page for the site when I thought to set up GA. After that had been done, I clicked on the link for 404 stats, which opens in a new tab. It churned for a long while and then showed a nearly blank page, similar to that when Firefox chokes on a badly-formatted XML page, except there was no error msg. But i was logged into the server and could see that that page has a 401 Transitional DTD. Strange!

I tried viewing source but it just churned endlessly. I then tried "inspect element" and was able to see an error msg having to do with some internal Firefox lib. Unfortunately, i neglected to copy that. :-(

All further attempts to load anything on the site would time out. Firebug's Net panel showed no request being made. Chrome would time out.

So, I deleted the GA profile, removed the JS block, and cleared the server cache. No joy.

I then removed all google cookies and disabled JS. Still nothing. No luck in any other browser. And now my client couldn't access the site. Terrific.

I was able use wget while logged into another server. The retrieved page was fine, and did not contain the GA JS block. However, the two servers are on the same network. (Perhaps a clue.)

The server itself was fine. Ping, traceroute looked great. I could SSH in. I tailed the access log and tried a browser request. Nothing. But i forgot to quit and a minute or so later I saw a request from someone else being logged. Later, I could see that requests had been served all day to some people.

Now, 24 hours later, the site works once again, but is still unreachable by the client (who is in another city).

So, does anyone have some insight into what's going on? Does this have something to do with google's CDN? I don't know very much about how GA works but what I'm seeing reminds me of DNS propagation issues. And why the initial XML error? And why the heck was the site just plain unreachable? What did google do to my site?!

Sorry for the length but I wanted to cover everything.

Answer 1

Sounds like a DNS propagation issue. When it is not fully propagated, the site my load or may not. It loaded once and you thought it was ready. But then it failed and you thought you (or Google) did something wrong.

If you are going to work on a site that you just changed the DNS or bought the domain name, it is good idea to change the DNS file on your local machine to point to site's IP. This, or just wait for propagation.

Answer 2

I'll second rlcabral's answer. Google for "dns check online tool" and use one or more of the services that allow you to check your (external) dns setup.

Google's current asynchronous JavaScript tracker snippet should not delay page rendering but verify if you have other external libraries or ad server code included. The more of it, the worse.

As every computer has it's own local DNS resolver library it's possible that it works on one but not the other depending on when the DNS problem occurred and at what point in time the client did the inital request.

Answer 3

Sounds like a DNS error; clear/reset your DNS cache, wait a while, and you should be good to go!

Otherwise, try using an alternate DNS provider (8.8.8.8 and 8.8.4.4 for Google), making sure to again flushing your DNS cache (sudo dscacheutil -flushcache on a Mac). It might be that there is something wrong being cached upstream with your ISP's DNS servers.