I'm running latest Raspbian Lite on Raspberry Pi 3 B. Just reinstalled ntpd completely and it doesn't synchronize time with upstream NTP servers at all.
ntpdate -u 0.debian.pool.ntp.org
works just fine. Using tcpdump (for eth0 interface) I can see that with ntpdate there are NTP packets going both ways, but with ntpd there is no response from the upstream servers (0...3.debian.pool.ntp.org servers set in ntpd config). When ntpd is running, using ntpq -p I can see:
remote refid st t when poll reach delay offset jitter
==============================================================================
0.debian.pool.n .POOL. 16 p - 64 0 0.000 0.000 0.001
1.debian.pool.n .POOL. 16 p - 64 0 0.000 0.000 0.001
2.debian.pool.n .POOL. 16 p - 64 0 0.000 0.000 0.001
3.debian.pool.n .POOL. 16 p - 64 0 0.000 0.000 0.001
What may be the source of this problem?