It may sound dumb...
But have you tried to ping a server from ssh?
I can't test for sure, but from ssh I can't ping anything, all packet are lost...
root@lede:/tmp# ping google.it
PING google.it (172.217.16.195): 56 data bytes
^C
--- google.it ping statistics ---
8 packets transmitted, 0 packets received, 100% packet loss
I have just flashed last firmware on a 2 version old firmware keeping settings, logged on ssh and pinged google ( as well as other servers )