we have few websites (each site for each client--uses same asp.net code but each site uses a different database), which is running (load balanced) across diff web servers. in few sites, when users were working in web site (any page) automatically they were redirected to login page when clicking links/buttons,etc. happens across sites/servers. once logged again, they are fine for few mins or hrs till it reoccurs.

what i need to look to fix this session or cookie expires problem? i checked iis logs it didnt give much info.

please help, thanks in advance.

How are you persisting the user's login information? In a cookie or in session?

If it's in the cookie, then I'm not sure what the problem could be. The cookie will be sent to any browser in the web farm so that shouldn't cause a problem.

If you are using session then what type of session management are you using? If you are using In-Proc than it is likely that your users are getting bumped from one server to another and thus their session data is not there on the other server. You can use SQL bases session state to eliminate this problem.

-Peter

thanks, we use cookie to store user info.

but also we use inproc for sessionstate, but if we change to sql base, what are the disadvantages? any performance issues?

In process will always be faster. Will you notice the difference? Probably not. I have used SQL server session state and can't say I notice the difference. Your load balancer slows down the application too, but some small amount, but you probably don't notice that.

Typically, what slows down your application is the application itself. The performance difference using SQL session is negligible and necessary in order for the application to be scalable.

-Peter