I'm new to IP Boards and I'm trying to get it up and running. I'm using nginx and PHP-FPM. The site runs even with friendly URLs but the issue is users can't login to the public side.

The page just refreshes and they are not logged in. I've tried wrong login info to make sure it was doing stuff and it works.

I'm pretty convinced that it had something to do with my nginx configuration.

The others I've tried were:
try_files $uri $uri/ /index.php;
try_files $uri $uri/ /index.php?q=$uri;
try_files $uri $uri/ /index.php?q=$request_uri;

I have been running WordPress, MediaWiki, phpBB and OpenX with the above config and they all work.

My nginx configuration
http://pastebin.com/qKm3N2ff

If its only public side then it may well just be cookies. The effects of this (does not effect admin panel) are you appear to be logged in and are thrown out immediately or you enter the correct login details but when the page refreshes you're not logged in.

Check this article I wrote a while back > http://community.invisionpower.com/resources/articles.html/_/ipboard-3x/tips-and-tricks/cookie-settings-r463 , its out of date now but the settings still apply.

Ensure you set the Cookie Domain and the Cookie Prefix

The domain should have a leading . that's intended and the prefix, leave the path empty for now. Ignore the Tools / Settings part of the article.

Try to login again after adjusting them.

My cookie domain is set correctly.

One thing I noticed was being on a page like

http://banhammer.us/index.php?app=core&module=global&section=login&do= process

I am able to login and the toolbar shows my username and the notifications icon, etc. As soon as I go to any other page then it looks like I'm not logged in.

you running nginx alone or proxying?

I'm running it stand alone behind Varnish but bypassing it.

thought maybe varnish was involved, varnish did the exact same thing to me even when bypassing it for the domain.

didn't matter if I was using apache or nginx, with varnish involved people logged out unless furls were turned off.

Yep, it was Varnish and it was completely my fault, I was stripping cookies >_< from everything.

Once that was removed, no issues and I took some snippets for my VCL from another post, that I didn't see last night.

http://community.invisionpower.com/topic/328398-unbelievable-results-with-varnish

tried that too, still was messy for me.

with me it happened whenever anyone hit an ip.content page, and am have content as default app using constants.php, unless furls disabled.

disable them and all good, except all the incoming links that failed then LOL