How to block Nintendo System / Firmware updates

This method will still allow you to use online features.
I did testing on all games and online features worked.

This is for temporary use till atmosphere and switchbrew codes are updated to work on newest firmware versions.
The online games may force you to update at later time.

you need to add this in default.txt in the hosts folder in atmosphere folder on your SD card.

block nintendo updates

127.0.0.1 receive-%.dg.srv.nintendo.net receive-%.er.srv.nintendo.net
sun.hac.%.d4c.nintendo.net
atumn.hac.%.d4c.nintendo.net
127.0.0.1 sun.hac.lp1.d4c.nintendo.net
127.0.0.1 atumn.hac.lp1.d4c.nintendo.net

then make sure you enable dns mitm

add those in your system_settings.ini in folder config in your atmosphere folder on your SD card.

[atmosphere]
enable_dns_mitm = u8!0x1
enable_dns_mitm_debug_log = u8!0x1

better situation

I have router with openwrt and I decided to go with dnsmasq

add those lines to your dnsmasq.conf in /etc
address=/sun.hac.lp1.d4c.nintendo.net/1.3.3.7 address=/atumn.hac.lp1.d4c.nintendo.net/1.3.3.7

then do as root or use sudo before the command.
/etc/init.d/dnsmasq restart

credits

Thanks and Credit to: https://github.com/kinnay/NintendoClients/wiki/Server-List