In my ASP.NET project, I am using Forms authentication. My main.master using LoginStatus control and web.config is set up for "Forms" authentication mode.
Before I log in, the control shows the text as "Login." After I log in, the control shows the text as "Logout." This is expected. However, after clicking around on a few links within the site, the control suddenly starts showing "Login" although I am still logged in. The session is still alive as some of the pages I visit dumps some session information.
Would appreciate if something can point me in the right direction. Regards.
If you are trying to redirect after setting a Session variable using
Response.Redirect("YourPage.aspx");
this may be causing the session token to gets lost, try using the overloaded version of Redirect:Response.Redirect("~/YourPage.aspx", false);
Another problem also may be miss configuration of application pool. If the application pool is configured as a web farm or a web garden (by setting the
maximum number of worker processes to more than one) and if you're
not using the session service or SQL sessions, incoming requests will
unpredictably go to one of the worker processes, and if it's not the
one the session was created on, it will get lost.
The solutions to this is either not to use a web garden if you don't need the
performance boost, or use one of the out of process session
providers.
For more information you can check the link of the original article below: http://weblogs.asp.net/bleroy/Don_2700_t-redirect-after-setting-a-Session-variable-_2800_or-do-it-right_2900_
Related
I have a web application developed in asp.net
The application has a "logon" portal where I record users logging on. However, I don't really know when they have exited the web application as they could just shut down the browser, rather than using the "logout" option. As IIS keeps track of session variables for a finite period when users logon, I thought a really useful option would be to use my ASP.net application to interrogate IIS for the value of all session variables, thus telling me who is still active via their session variables.
This could be very useful when it comes to dropping in an upgrade to the website and generally looking at the use of the site.
Thanks
session object. But it only tells me about the current user.
I have a web application (.net VB code) that utilizes session variables to store the username (here login name) and the profile (admin/client), authentication is handeled by asp membership. The application then relies on these session variables on the load events. This application has been running fine for a couple of years. However, recently users complain about occasional error messages after logging in and attempting to load a new page that needs one of these variables. It happens most frequently Chrome, but also IE and Firefox.
Users that experience the error need to log out and clear the browsing history, after that it works again. The error is not easy to replicate - I was able to trigger it on my machine 'violently' using the 'back' button a couple of times that eventually tripped it - then I had to clear my browsing history to get the application to work again.
What might cause this to happen?
the session gets set on the load event of the 'login' page with 'Session("Type") = "Admin"' and subsequent pages check for the value of Session "Type"
I understand that I could use a cookie instead, but I chose not to for security reasons. Could this be prevented using a cookie instead? or do I need to use the membership.getuser method to get the username and then look up the values in the database? That does not seem efficient.
Ideas?
FYI, the ASP.NET Session ID is stored in a cookie that travels back and forth with each request/response. The actual session state values for a given session are not stored in cookies ... they are stored on the server only. They could be stored in memory, or in a SQL database, depending on how you've configured ASP.NET Session State.
But Session State can get destroyed for a variety of reasons. IIS might suddenly decide to restart your Application Pool, for example, in which case all your Session State would be gone.
Basically, you need to write your web app to always handle the possibility that Session State may be empty. If it is empty, then you probably need to redirect the user to the login screen to enter his credentials again.
Clearing the browsing history should have no effect, so I can't explain why that would help get past the problem.
I have the oddest situation...
On my ASP.NET website when the application pool recycles the user is logged out. This is fine. I know this is suppose to happen. But when the user logs back in and selects any link within the website, they are logged back out immediately. They consistently get logged out. I don't know what causes this and I don't know how to fix it.
The odd part is the work-around. If I log in from a different computer or from the IIS Server itself than the user that is getting logged out can log back in.
Does anyone have any ideas as to what is happening?
Standard Forms Authentication in ASP.NET is cookie-based and should not be affected by the session vanishing. But, you're probably relying on something in the session to determine whether or not the user is logged in. If you're using in-process session storage (and it sounds like you are), then your application code might act strangely if you get in a state where the Forms Authentication cookie still exists and is valid but the session information is missing. Instead of going to a different computer, try blowing away your cookies and logging in again, and I would presume that your issue is resolved.
One step is to move to out-of-process session storage (such as the ASP.NET State Server, which is simple to use with a few config changes) or to eliminate session usage entirely (by depending on values stored in cookies, though there are security implications there to consider if these values are not encrypted). Then, take a close look at how your application code handles the condition where a login cookie is set but the session data is invalid.
It's a shot in the dark based on the information provided, but hopefully it puts you or someone else on the right track.
I discovered the problem. In the Security settings of the ASP.NET Configuration each user that logs in needed to have one of the roles defined in the "Description" field. This is very odd to me be but it seemed to do the trick. Anyone know why this needs to be done?
We have a web application running on ASP.NET 3.5. It is viewed by the world as one URL but in reality there are multiple IIS boxes hosting the application controlled by a load balancer.
My problem is that it is a sensitive application with strict security controls around it, and that post authentication if you open another browser to the same application and log in as someone else, the second login overwrites the first logins' session id value in the cookie, and then the first window crashes.
Any idea how I can get around this?
The session ID is placed in the cookie. If another browser window is opened and starts a second session the ID in the cookie will be replaced.
Also, logins should not be controlled via the session cookie. There is a Forms Authentication cookie for that purpose which is more secure as I recall.
Most web applications only allow one session per PC. Try logging into Yahoo Mail, Amazon or Ebay twice on the same machine and you will find the same problem. So ASP.NET is pretty much designed around the idea that there is one login per PC. Although, if you have multiple browsers installed on a machine, you can generally log into apps more than once because each browser keeps its own cookie collection.
edit: You might want to try cookieless sessions, in theory they might allow multiple sessions per PC, although I haven't tried it. But cookieless sessions come with plenty of problems and limitations of their own.
In short, there may be some hacky way to do what you want to do, but it will probably be fiddly and cause other problems elsewhere, because what you are asking for goes against the grain of ASP.NET's core design.
I have an asp .net webforms app that uses forms authentication. For a small number of users we have a problem where they log in, they navigate to a couple of pages and then they are asked to log in again. Once logged in for a second time they seem to be able to stay logged in as expected. They shouldn't be asked to login the second time.
This is a single server, no web farms, nothing tricky.
This only happens to a few users, but it does seem to be all users from the same building. I am unable to replicate this and at this point might even start to deny that t was happening if one of our trainers hadn't watched it happen to a couple of customers.
Has anyone else seen anything like this?
I am also seeing a lot of "Membership credential verification failed." errors in the event log. This may be related, but all the googling I've done seems to point to web farms and the like, not a single server.
UPDATE
There is no proxy server, the IIS server and the browser (IE8) are both on the same machine.
The AV software installed is Symantec Endpoint, on one machine, on the other the user didn't have any AV at all (AV Fail!).
The browser is IE 8 with no frills, not a single addin that didn't come with the default installation.
Both session and user login time-outs are set to 30 mins and the problem happens within 1 min of the user logging on.
Logging shows the user to only have one IP address.
I have tried the sessionMode in all it's variations, this doesn't seem to make any difference.
Something has to be causing ASP.NET to think these users have new sessions or their authentication cookie is getting invalidated. Here a a few things I can think to check:
Are the users accessing the site through a proxy server? One of our customers has a proxy that will sometimes close all open connections causing ASP.NET to see the session as new.
Could an overly agressive anti-virus, anti-spyware product be "eating" the session authentication cookie?
Do they have a cookie manager browser add-in that is causing the authentication cookie to disappear or change?
Sounds basic but I've seen this happen because of site timeouts being set too short. If the user sits on the page for longer than the timeout, they will be forced to logon again. And this could be specific to a page when that page presents a large amount of data that takes a while for them to go through.
One other thing I just thought of, have you allowed multiple worker processes for the ASP.NET process (aka web gardens)? If so, the same constraints as with a web farm would apply for authentication.
Crack open Fiddler from the problem user's PC and see what's getting passed in the headers. My bet is on a proxy server and or networking issue.
Are the users possibly coming from a dynamic ip address? I've seen problems where the users sessions get messed up because the IP address that they're accessing the site from changes for some reason.
Are the people this is happening using a browser that's somehow different (different browser, different version, different extensions)? That could be a clue.
In general, when the problem is somewhat reproducible or at least predictable, I use Http Fiddler. Install it on a client machine, turn it on, and start browsing (this works via a system proxy - so it'll work for firefox, IE and any other proxy-supporting browsers alike). Fiddler will record all http traffic between client and server, and you can then peruse such a session later on to find any oddities.
It's a long shot, but one thing I've seen happen occasionally that can lead to these sorts of unpredictable errors is scripting parallelization issues: sometimes buttons + links have onclick handlers which cause a post-back. If you have several such handlers that fire on the same event - in particular when the default event still fires additionally to your custom onclick or whatnot - you may be causing several postbacks when it appears to be just a single postback. That can cause all kinds of unpredictable weirdness as it's not entirely clear which request ends up "winning" - and some odd errors may cause a session to terminate. Since this behaviour is very browser + network latency sensitive, it seems quite unpredictable when it occurs.
Delete the cookie on the client PC's that are playing up
ASP.NET Forms Authentication can redirect users to the login page if they do not have the credentials to access a specific page. It does this so that users who may have more than one login are given the opportunity to login with another account which may have the appropriate access. Basic question I know, but are the users using the same credentials the second time they log in?
Its possible that you have don't have specifically specified asp.net to use cookie based session but are allowing either cookie or cookieless sessions.
In the later case the session id is embedded in the Url. The type of issues you are experiences might be explained by that. Basically depending on how you define your links, some of them would not get the session id, so the user would get a new session when using those links - or maybe during a redirect. That could explain why at specific parts of your site the users loose their session.
If you have the mixed mode enabled, try setting it to only cookieless and go through your site.
Update: Based on the extra info posted there is surely more info needed for it. Some extra things to check:
Are you using subdomains, if that's the case the cookie might not be configured to allow that and that doesn't fail in all environments.
If you are using in-process session, make sure there isn't a bug in the application causing it to restart the process
Maybe what's causing it to ask for login again is an authorization check, and you have an issue on some roles related code
Is it possible that the user is just opening a separate window? ;)
To rule out the possibility of the browser or a browser addon messing things up, have you checked their User Agent strings? If they are randomly distributed it might not cause the problem, but if they're all the same, this might be a hint too.