yandex.com/AAAA: No response was received until the UDP payload size was decreased, indicating that the server might be attempting to send a payload that exceeds the path maximum transmission unit (PMTU) size. See RFC 6891, Sec. 6.2.6. (2a02:6b8::1, UDP_-_EDNS0_4096_D_KN)
yandex.com/NS: No response was received from the server over UDP (tried 7 times) until the NSID EDNS option was removed (however, this server appeared to respond legitimately to other queries with the NSID EDNS option present). See RFC 6891, Sec. 6.1.2. (2a02:6b8::1, UDP_-_EDNS0_4096_D_KN)