Question

I have a bit of a strange issue that maybe someone can shed some light on.

I have an RUT950 setup to provide me with remote access to some security cameras. Internet at the remote site is provided by 4G, it has a routable IP, all the right ports are forwarded, etc.

I can view the cameras with no issues using the application on my desktop computer, and also from the application on my phone - so long as my phone is connected to a wifi internet connection (whether at home, at work - doesn't matter). As soon as my phone is on cellular data, I can't view the cameras - the connection just times out.

There aren't any IP restrictions on the firewall/port forward rules that allow the inbound connection so I should be able to access them from anywhere. With the previous 4G router that I had at the site I didn't have this issue, so I am 100% confident that it's not blocked ports on my mobile carrier's network. The only thought that has occurred to me is that my phone's carrier (Telstra here in Australia) uses CGNAT for their mobile devices so I don't have a routable IP (although it does appear to be a class A using whatismyip.com; currently it's 1.143.x.x) and I'm wondering if there could be something in the RUT950  firewall that is preventing access because of this.

I have turned off the RFC1918 filter under System -> Administration -> Access Control but that's made no difference. I've been kinda stumped on this one for a while.

Does anyone have any suggestions as to how I could figure out what's going on and resolve it?

Answer 1

Hello Ben,

First could you tell me, can you reach router GUI when using Mobile connection and not wireless?

Secondly, is SIM cards on router and on phone are from same provider?

And finally would it be possible for you to try connecting to router/camera via mobile connection few times, from home, then after that, login to router from home network download Troubleshoot file from System > Administration > Troubleshoot tab, and send it to me via PM here?

Best regards,
VidasKac.

Comments

Thanks VidasKac

Last night I actually did a bit of googling and found a post on Telstra's crowdsupport forums saying some additional ports might need to be forwarded to resolve an issue with mobile app access from Telstra SIM cards. I didn't actually have the FEN port forwarded (and never needed to with the old Telstra 4G router) but I forwarded the extra ports this morning and lo and behold it now seems to work.

Seems like I was barking up the wrong tree with the RFC1918 thing after all. 

Thanks for the help, I was fully expecting to send you logs this morning - much appreciated :) 

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Hello Ben,

Glad to hear that issue was resolved, and I hope RUT950 will serve you well.

Best regards,
VidasKac.

Answer 2

Disable DNS rebind protection maybe?

Comments

Thanks mate. Turns out that was already turned off (I don't remember doing so) so that wasn't the issue. Looks like I just missed a couple of ports that needed to be forwarded! Silly, but at least it's fixed.