Hi. This has to due with my last thread (https://community.tp-link.com/en/home/forum/topic/653186?replyId=1332702), but, as it is more related to IPv6, I start this new one.

 

After trying the suggestion of using the 3 Decos as access points (putting a router before the Deco M5), the problem persisted. So, after lots of new attempts, finally I could solve the problem: in fact, the problem was the IPv6 config and a probably IPv6 conflict with Android Devices (specially, the 4 Mi Boxes).

 

I figured this out when, after another crash of the internet connection, I could still access the router (TP-LINK EX220, provided by the ISP) via DDNS, and realized that the status didn’t show any IPv6 address. Hence, the internet was active, because I could still remotely access the router (gateway), although I didn’t have internet connection via wi-fi or ethernet cable.

 

This was my ISP’s router config when I had the internet problem:

 

 

- On internet config, the IPv6 addressing type was SLAAC.

- On LAN config, the IPv6 address type was RADVD.

- Status didn’t show any IPv6 address or gateway.

 

As an example, I had this status on a Mi Box:

- 1 IPv4 address.

- 3 IPv6 addresses.

 

Furthermore, perfoming IPv6 connectivity tests on this website (https://test-ipv6.com/) with all my devices, I had IPv6 address on my laptop (Windows), on my smartphone (Android) and on all the Mi Boxes (Android). However, the internet connection always dropped randomly (probably, due to IPv6 conflicts).

 

So, I tried another config:

- On internet config, I set the IPv6 addressing type to Auto.

- On LAN config, I set IPv6 address type to DHCPv6 server.

- Status now show IPv6 address and gateway.

 

On the Mi Box, now I have this status:

- 1 IPv4 address.

- 1 IPv6 address.

 

However, perfoming IPv6 connectivity tests on this website (https://test-ipv6.com/) with all my devices, I still have IPv6 address on my laptop (Windows), but no IPv6 addresses on my smartphone (Android), nor on all the Mi Boxes (Android).

 

Googling why this happened, I discovered that Android isn’t compatible with DHCPv6 server. Ok, I understood this.

 

What I still don’t  understand is what persistently happened with my internet connection using SLAAC and RADVD. Looks like IPv6 conflicts, but what is the technical explanation? What is the error cause? I wanna understand what was really going on.

 

Thanks, brothers.