Yesterday, I added the free CDN services CloudFlare offers to my forum. I used all of the recommended settings. The used bandwidth dropped drastically and the site loaded a lot faster so I was pretty happy. But then (a small) percentage of the users told me they keep getting logged out automatically.
I lowered the caching settings and a few people stopped getting logged out, but not everybody, so I disabled CloudFlare. Is this a known issue? Google didn't tell me anything useful. And is there any way I can enable it again without getting this issue?