no allow duplicated login

northcloud

Hello, does anyone know how to avoid duplicated users in members system on your website login on same computer or multiple computers ? That is if a member login the system, no one else is allowed login with same name and password at same time. Members may loggout or just close window ending task. Someone told me using session to control, but it doesn't work well. Any one has advices? Thanks in advance.

planetsim

😕

Ok are you talking about Users on the computer or users in members system on your website?

If so when a user logs in you can have an extra field called logged_in or something similar so when they login logged_in is 1 and if they are logged out logged_in will be 0.

Not sure if thats what you want but it beats sessions as you cannot always be 100% sure with them.

northcloud

Thanks,planetsim. I am talking about the users in members system on your website. If I use login flag, when user click 'logout' link on my site, I have chance to set login flag as logout. how about member don't click loggout link, just close the window? In that case, I dont have chance to set login flag and it means this member couldn't log in any more since the the status is login already.

Roger_Ramjet

Well, you use an html event script that runs when the document unLoads. This script handles the logout for the user. It would run if they close the window, or if they just surf away from your site, that's the document unload bit. You will need to know some javascript, not much, just enough to write a function that calls your logout script, which unsets the flag. Can be made almost invisible to the user.

Have a look at html events and folow the links to their javascript tutorial.

If your java is not up to it, you could easily find a script in a javascript forum that does it for you.

TheDefender

Alternative:

If running on a *nix based box, you can create a script to run as a cron job which basically resets everyone's bitt flags back to 0 automatically like every 10 minutes or so.

If the user is on while their bit is set to 0, and their session is still active in their browser, then on the next page load, it will set the bit back to 1. If they close their browser, then their session ends, and obviously, their bit would stay at 0.

With this method, the worst case scenario would be they can't log back in for x number of minutes (however long you have between the cron jobs running.)

northcloud

Thank you guys. I will try like you suggested.

northcloud

Hello, TheDefender, Could you tell me what is 'a *nix based box'? I don't know about it. Thanks.

TheDefender

nix is something like a Unix or Linux based web server. CROM is a daemon that runs on a nix based server. It isn't available on Windows based servers, although there are some apps that can mimic this, but unless it's your own server, you can't really install and run these types of apps.

If you google CRON or search for CRON on these forums, you should find some helpful info about it. (Again, your webserver needs to be a *nix based server for this to work), so before you pursue that thought process, you need to confirm this with your host. You also need to confirm it with them that you (as a user) have the ability to setup and execute CRON jobs.

northcloud

Thanks, TheDefender. I see a crontab button in my host's control panal, I think that is what you mention. I will check how to use it.