We have recently moved many of our websites to a new ARR webfarm cluster.
Since then, some of our websites have been experiencing duplicate requests.
That is to say, someone clicks an "add" button on the browser, the page takes a long time to return and the result is more than one record created in the webapp.
The log file from the webserver shows 3 identical requests, approx 30 seconds to a minute apart, taking 0.2 seconds to complete.
The log file from the arr server shows also shows 3 identical requests, the first 2 taking 16 to 18 seconds, the last taking 0.2 seconds to complete.
Its as if the client is clicking the add button 3 times, or pressing refresh on the browser twice, but this is not the case. We added a parameter to the querystring to show the current time in milliseconds, but that is identical in all cases of duplication.
The websites all worked fine prior to the move. They are a mixture of .net and classic asp
Anyone got any ideas?