Dear lwip comunity. Recently I faced some trouble with using lwip in my
project. Last time I am using lwip 1.4.1 with in esp8266 and it can connect
to some wifi AP but when I moving my project to using lwip-2.1.2 stable it
make my esp8266 can't connect to the internet with the same wifi AP as lwip
1.4.1. After alot of try and observe i figure-out that, lwip 2 still can
work with that AP but i need to recompile lwip2 with modify IP_DEFAULT_TTL
to (0x80 or 127) instead of using default value is (0xff or 255) I guarantee
that it is true. So is it necessary to make IP_DEFAULT_TTL 255??? can you
just change it to 127 as default. because maybe some other guy will face
this trouble like me in the future. (the wifi AP i am using is Blink
BL-WR1000).