Email being blocked on wifi devices only when VPN active?

[Dazzler]

Merlin Firmware - 386.5.2

Preamble - I have my ASUS RT-AC86U setup to use NORD VPN and want all (most) traffic within the house to go to the outside world via the VPN.
Problem - I get email server rejections and am unable to access my email via the VPN but can over the WAN i.e. VPN disconnected.
Solution? - So I thought I could put all of my IP range (1) via the director rules to use the VPN then simply allow the IMAP and SMTP servers (2) to be accessible by all devices as per the image below. This works with my PC (10.0.0.49) on an ethernet connection but not my WiFi devices unless I exclude them from the VPN explicitly as shown (3).

Question - Why would the WiFi connected devices not be able to respond the same way as my ethernet connected device as they are all in the included IP range? - Or is there something more fundamental that I'm missing here?

TIA for any help/suggestions. Pls be gentle - I'm new to this game.

 

[eibgrad]

Not sure if this will make the difference, but *technically* your "All traffic" entry is incorrect. It should be 10.0.0.0/24. The firewall will accept this sort of error and handle it correctly, but the routing system tends to be more sensitive to this kind of error. To be on the safe side, you should correct it.

 

[Tech Junky]

Why would the WiFi connected devices not be able to respond the same way as my ethernet connected device as they are all in the included IP range?

It shouldn't make a difference within the sane subnet. Although I've seen some funky routing issues in the past where my server "router" can connect to my cable modem interface / GUI but, clients attaches can't. Looking at the routes on the server looked fine as did the routes on the clients. Sometimes there's an additional mechanism that blocks things., Now, e-mail being externally hosted would come down to rules usually.

There was a period of time a while back though that I had an issue with US based servers not passing TLS and causing issues. I tested a few different countries to see if it was system wide on Nord's side or just one region. Well, I stumbled upon a couple of countries that worked just fine and used them while debating the issue with Nord. We went back and forth for maybe a month and a half on the issue and eventually it got resolved. Knowing that they use "live images' and not HW based storage for the OS / configuration lead me to believe someone that makes the images borked a config within it. Snice the scope of the issue was limited to certain regions pointed to the image being used.

Never did get a straight answer on what the resolution was. While testing though i tried different versions of the app for linux to make sure it wasn't the SW on my side causing the issue. Oh, and the OVPN version worked but, the nordlynx option didn't. But, chopping BW by 50% to use OVPN domestically didn't make sense.

 

[Dazzler]

Not sure if this will make the difference, but *technically* your "All traffic" entry is incorrect. It should be 10.0.0.0/24. The firewall will accept this sort of error and handle it correctly, but the routing system tends to be more sensitive to this kind of error. To be on the safe side, you should correct it.

Thanks for the response. I did make the change you proposed but unfortunately it hasn't made any difference to the original problem - but thanks for the suggestion nevertheless.

 

[Dazzler]

It shouldn't make a difference within the sane subnet. Although I've seen some funky routing issues in the past where my server "router" can connect to my cable modem interface / GUI but, clients attaches can't. Looking at the routes on the server looked fine as did the routes on the clients. Sometimes there's an additional mechanism that blocks things., Now, e-mail being externally hosted would come down to rules usually.

There was a period of time a while back though that I had an issue with US based servers not passing TLS and causing issues. I tested a few different countries to see if it was system wide on Nord's side or just one region. Well, I stumbled upon a couple of countries that worked just fine and used them while debating the issue with Nord. We went back and forth for maybe a month and a half on the issue and eventually it got resolved. Knowing that they use "live images' and not HW based storage for the OS / configuration lead me to believe someone that makes the images borked a config within it. Snice the scope of the issue was limited to certain regions pointed to the image being used.

Never did get a straight answer on what the resolution was. While testing though i tried different versions of the app for linux to make sure it wasn't the SW on my side causing the issue. Oh, and the OVPN version worked but, the nordlynx option didn't. But, chopping BW by 50% to use OVPN domestically didn't make sense.

When I get the opportunity I might change the Nord server location to test out your theory/past experience to see if it is problem with an image at their end.
Seems odd though that only the WiFi devices are having the issue though?! My 'gut' feeling is that it's within my router. I didn't really want to reset to factory and reload from scratch but might have to.

Having a VPN that I can't use if I want access to email full time, renders it useless. I'll keep tinkering unless there are more ideas from the experienced out there for me to try? Thanks.