Have a strange one here I can’t seem to figure out and hoping someone may know the answer. We have some users who are unable to view our forum when connected on mobile data, with no issues when using a wifi connection. I have validated a users IPv4 and IPv6 addresses and neither are blocked under screened_ip_addresses, and they have no issues accessing another instances of a discourse-based forum or other websites, so I put it down to a setting somewhere in our forum.
I am trying to gather more user data to check this, but in the meantime would anyone have an idea why this could be happening please?
That is a weird one. One thing worth checking is whether the mobile provider is the same for all these users and if it has put your site or IP range on some kind of blacklist. It would explain why several people hit the same issue on mobile data but not on Wi-Fi.
A few other things that can sometimes cause this:
mobile networks often default to IPv6, and if the server or proxy isn’t handling it properly, connections just fail.
if you’re behind Cloudflare (or another CDN/firewall), it might be mistakenly blocking some mobile IP ranges.
SSL/TLS quirks, some carriers still have issues with certain certificates if the chain isn’t perfect.
I’d try to gather from the users which providers they’re on, and whether they’re seeing the problem with IPv4 or IPv6. That should help narrow it down.
Thank you for your suggestions on this. I will reach out to the community and try to gather as much information from them as I can based on your points and see if there’s a pattern here.
I did a forum migration several months ago and several users couldn’t connect to the forum from their mobile network (it worked fine over WIFI) until they cleared their browser’s cache.
I’ve run through some tests with the community members having the issues and still nothing yet, so wondering if maybe someone has another idea they can think of. So far we’ve:
Removed any blocked IPs that were done when the problems started to be sure there’s no issue there
Asked all users to clear their browser caches and flushed the DNS settings
Confirmed they are all not using the same carrier for data
Tried multiple browsers and same results
One very odd thing that happened is that one user was not able to access it on the phone, but when using it as a mobile hotspot another device was able to access it no problem! I cannot work that one out at all. It’s a very small amount of users, but I’d like to get this sorted in case it is meaning other people looking to join may not be able to because of it.
We haven’t been able to resolve it yet. The users get the err_timed_out error, but it’s only received on their mobile carriers. I’ve asked them to let me know what carriers they are on, as the problem seems to be specifically for US users and it appears that they all seem to be on the same one. What I think has happened is our forums IP address is being blocked by their carrier for whatever reason and they cannot connect.
Still doing some further testing to confirm if other users with the same carrier are able to access it, to determine if it is actually that or an unusual per-user problem we’re going to try to fix. I’ll update when I know more though.
Thanks for the reply again Tobias. We’ve done some testing and believed it was a carrier issue - however a user had someone test on the same carrier and it work without any issues. Right now I’m thinking it’s a case-by-case for each user, and each one has a problem unique to them. Will continue to test and let you all know if we can get it working and what the root cause of this mystery was.