Disable/enable NAT Loopback?

[FredTheFrog]

https://www.snbforums.com/threads/cant-get-snat-masq-to-work.80170/ is a good reference thread.
Thought I should mention it, instead of reviving a year-old discussion that appears solved.

In later versions, Merlin v388.2_2 to be specific, on the RT-AX88u router, there is no NAT acceleration option/setting, nor is there any ability to enable/disable NAT Loopback. I'm asking here, how can I disable NAT Loopback to perform testing, and then re-enable it afterward? Currently, NAT loopback does NOT appear to be working correctly.

 

[ColinTaylor]

https://www.snbforums.com/threads/cant-get-snat-masq-to-work.80170/ is a good reference thread.
Thought I should mention it, instead of reviving a year-old discussion that appears solved.

In later versions, Merlin v388.2_2 to be specific, on the RT-AX88u router, there is no NAT acceleration option/setting, nor is there any ability to enable/disable NAT Loopback. I'm asking here, how can I disable NAT Loopback to perform testing, and then re-enable it afterward? Currently, NAT loopback does NOT appear to be working correctly.

The thread you referenced was dealing with a very specific problem using a VPN client. Are you having this problem?

NAT loopback should work fine, there's never been an option to enable or disable it. Can you describe exactly what you're doing that doesn't work?

NAT acceleration was never a configurable option on the AX routers, that was something that only applied to the pre-HND (ac) routers.

 

[FredTheFrog]

The thread you referenced was dealing with a very specific problem using a VPN client. Are you having this problem?

NAT loopback should work fine, there's never been an option to enable or disable it. Can you describe exactly what you're doing that doesn't work?

NAT acceleration was never a configurable option on the AX routers, that was something that only applied to the pre-HND (ac) routers.

I realize it was a very specific problem, but the subject matter is relevant. I have a Home Assistant server with LetsEncrypt SSL certificates running inside my LAN. Previously, this i3 NUC was running Debian 11 Bullseye and hosting Home Assistant within Docker containers. Everything worked great, both within my LAN, and outside my LAN. Home Assistant has smart phone apps that use either internal LAN or external DNS addresses, and NAT Loopback worked great when using my external DNS node name within the LAN. I could use my laptop and browser within the LAN to do anything on the Home Assistant server.

I switched from Debian 11 to the Home Assistant OS, a variant of Linux pre-packaged by the Home Assistant application group. I just didn't want to deal with managing the OS any longer, trying to simplify things. When bringing up the new OS and application, I restored a backup of the HA application to get things running again. Tweaked several settings in the HA OS interface, and it's working great with the phone apps so long as I hit them from outside the LAN. If I use my laptop and browser from within the LAN, I get timeouts and no GUI. So for some reason, the NAT loopback that previously worked with Debian 11 is no longer working with HA OS.

I was hoping to disable and re-enable NAT loopback using an IPTABLES command, to test whether this had any impact on the LAN access issue.
Similarly, I was hoping to disable and re-enable network acceleration, to test whether this had any impact on the LAN access issue.

 

[ColinTaylor]

As I mentioned above NAT acceleration is not relevant for your situation. Likewise the NAT loopback issue in that other thread was specific to using a VPN client address on the router. The normal NAT loopback is always present and is not configurable. As this was all working before you replaced your Home Assistant server I think it's safe to say that NAT loopback works fine.

I suggest you check that your port forwarding rules have been created correctly and your client is able to resolve your DNS name from inside your LAN.

 

[FredTheFrog]

Loosely following the instructions at https://github.com/RMerl/asuswrt-merlin.ng/wiki/Custom-domains-with-dnsmasq . . .
Corrected the issue by adding a JFFS file last night "/jffs/configs/dnsmasq.conf.add" containing the FQDN and the internal LAN IP address.

address=/my-custom-domain.dyndns.org/192.168.1.35