Can't discover external address in my Cone NAT

[songjiayang]

Here is my network NAT type check result:

16:36 $ natat
2019/04/15 16:37:21 start stun server ping...
2019/04/15 16:37:22 stun.l.google.com:19302 mapped: 0.0.0.0:3489 -> 101.84.176.17:25852
2019/04/15 16:37:22 stun1.l.google.com:19302 mapped: 0.0.0.0:3489 -> 101.84.176.17:25852
2019/04/15 16:37:22 start NAT type assert...
2019/04/15 16:37:22 It's Cone NAT

But run the example result is:

16:32 $ go run nat-tester.go 
2019/04/15 16:39:07 error: no NAT found
exit status 1

I am curious, why not use stun server to get pmp?

[Stebalien]

It's actually trying to discover the NAT device (your gateway) so it can configure it. Just knowing the external address won't really help.

[zhuwei]

@songjiayang 请教下，我这边也找不到nat。是为什么呢，还是说必须要连一个stun服务器？