Jio uses DNS sniffing and SNI blocking.
They monitor all DNS requests(no matter who provides the DNS server). So the solution is DNS over HTTPS.
The SNI method is a bit tricky. ESNI does prevent the blocking, but currently it’s rarely implemented by websites. One other solution is TCP fragmentation. Split the packet containing SNI into two. This prevents them from catching the whole URL mentioned in the SNI. Thus, they are unable to block it.
One such tool: https://github.com/SadeghHayeri/GreenTunnel
