Cannot access specific sites

Started by mtw86, July 18, 2023, 11:21:12 AM

Previous topic - Next topic
Hey all, greetings,

I'm new to custom firewalls and to this forum so if this is the wrong place, please let me know.

I managed to set up everything like port forwarding and other stuff.

I would also like to point out that I assigned a LAN interface as a bridge, I know this is not ideal but I do not see a lot of traffic.

Everything seems to be working fine except a few specific websites which are not reachable, one of which is the ISP website.

I am guessing that it's DNS related but I might be wrong.

Does anyone have an idea of what the issue might be? Any help is appreciated.

What do you mean by port forwarding and other stuff?

How did you configure the bridge?

Did the sites work before you made any changes?

July 18, 2023, 09:49:41 PM #2 Last Edit: July 18, 2023, 09:51:49 PM by mtw86
I have a NAS behind the firewall, and I connect to the NAS through VPN, so I had to port forward it in the WAN interface.

In the bridge setup I selected all the interfaces as members except the WAN interface.
In the LAN (bridge) interface I selected Track interface as IPv6 Configuration Type and Static IPv4 as IPv4 Configuration Type.
For IPv6 Interface I selected WAN from the dropdown.

I can access the sites only when connected through VPN.

I hope this helps.

What WAN technology do you use? PPPoE? VLANs? Probably you did not fix the MTU/MSS or do not use MSS clamping. That may result in some sites not being available because they use large MTUs but PMTU discovery does not work.

You can check if DNS is O.K. and ping the affected sites. If that works, but HTTP(S) does not, this is likely to be the problem.
Intel N100, 4* I226-V, 2* 82559, 16 GByte, 500 GByte NVME, ZTE F6005

1100 down / 800 up, Bufferbloat A+