I recently updated to the Beta 4.7.4 on my Flint 2 router. Mostly working well.
I set up ZeroTier (ZT) to Allow Remote Access to LAN according to the docs at NAT Settings - GL.iNet Router Docs 4
Immediately I was able to ping various IP addresses within my network from devices connected to ZT through my cell phone hotspot. However, I noticed things were slow.
Running zerotier-cli peers on client laptops from within the LAN and outside the LAN, revealed that UDP connections appeared to be blocked, and RELAY was being used.
After checking the laptops themselves (both of which had OS upgrades since I last needed ZT), I decided to look at the Router config. The only way I could establish DIRECT connections through ZT was by enabling Full Cone NAT.
Is there a way to allow UDP connections for ZT without needing to enable Full Cone NAT?