Skip to main content

Application deployed on a web farm - View state validation.

By default, ASP.Net 2.0 encrypts the data in the ViewState with a private key generated on the server. This key is unique to the server. So in a scenario where there is more than one server e.g. in a web farm, each server will generate its own key. This is where the trouble starts.

Consider there are 3 servers A, B and C. Say users first request is served by server A. Now when user posts the data back, say the request is sent to server B. Server B will now try to validate the data in ViewState with its own key. As the key is different to the one with which the data was encrypted, it will fail validation and will raise "Unable to validate data" error. To avoid this, configures MachineKey element in Web.Config for a cohosted website or in Machine.Config for dedicated server. Please see http://msdn2.microsoft.com/en-us/library/ms998288.aspx on how to configure machinekey.

DebugGuru
Labels:

Comments

MilPhilner said…
so, all servers use the same machineKey, right?

what about maintaining state?
22 August 2008 at 15:29
Post a Comment

Popular posts from this blog

Why there is semicolon at the start of a JavaScript function?

Very often while reviewing the code for my team, I will come across a semicolon at the start of JavaScript function as show below ; (function () { 'use strict'; ...and I often wondered what purpose it served. Guess what. It is an insurance to make sure your script works fine when all other scripts are merged together;  The leading ; in front of immediately-invoked function expressions (iffe) is there to prevent errors when appending the file during concatenation to a file containing an expression not properly terminated with a ;. So there you go. Now you know what that little semicolon is doing there in your code.
3 comments
Read more

C# Performance Improvement - The Power of StringBuilder

 Often when we are wring code we don't think about performance and go with the default options available to achieve a task. String concatenation is one such scenario. If you are doing simple and few string catenations, then you can use the following result = string1 + string2; string1+= string2; result = String.Concat(string1,string2); String.Format and string interpolation are few other options.  However when you are performing large and repetitive  operation, string catenation can be expensive. Here is an example to prove the point.  As you can see it took 41 seconds to perform 100k string catenation. Now lets replace this with StringBuilder and see.  8 ms!!!!!! That is a massive performance difference. Hope you get the point. More info on StringBuilder can be found here https://learn.microsoft.com/en-us/dotnet/api/system.text.stringbuilder?view=net-7.0
Post a Comment
Read more