Updating a Web Application in IIS - Best practices

Question

What are the best practices for updating a web application in IIS?

The first page you see when you visit our application is a login page.

What I want to achieve is that visitors be redirected to a page stating that the application is being updated. And for users with an admin role being able to login successfully (to check whether everything is working properly)

In web.config we keep track of wheter the application is being updated (updating = [true|false] and then on the authentication_event:

if (updating) 
{

   if (User.IsInRole("admin"))

   {

      redirect to main web app...

   }
   else
   {     

     redirect to web being updated page....

   }

}
else 
{

   redirect to main web app..

}

Any advise will be appreciated immensely..

Answer 1

Looks like you pretty much have it figured out.

if (WebConfigurationManager.AppSettings["updating"]=="true") 
   if (User.IsInRole("admin"))
       Response.Redirect("~/Main.aspx");
   else
       Response.Redirect("~/Updating.aspx");
else
   Response.Redirect("~/Main.aspx");

Answer 2

instead of doing it via web.config, you should be saving the updating flag in some other xml file or database, as each time you update your web.config file, your application restarts, thus invalidating current application variables, caches, etc etc

apart from that, you got the other logic right. but avoid touching the web.config as far as possible - i personally only save the connection string in the web.config as that hardly changes

but rest of the key value pairs which change often, i have them saved in sql database table. so that way i never ever have to do an application restart unless my connection string changes :-)

Answer 3

I test everything locally, then I use the built in app_offline.html file on production server. When this file is present it will be served to clients, in meantime I am uploading new content. When done, renaming app_offline.html to something different and the new app starts.