List of Monitoring IPs?

Server operators
9

As an additional data point, I started pinging the server too. Although these results are still preliminary, it looks like NTP packets get dropped more often than ICMP echo requests (pings).

Ping stats: Singapore, Netherlands, Australia, Finland.

Edit: There’s also a summary stats page.

You said you had disabled connection tracking, but please verify with “conntrack -L” or “grep port=123 /proc/net/nf_conntrack” (or whatever works for you), and/or “iptables -L -t raw” which should probably show something like:

Chain PREROUTING (policy ACCEPT)
target     prot opt source               destination
CT         udp  --  anywhere             anywhere             udp dpt:ntp CT notrack

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination
CT         udp  --  anywhere             anywhere             udp spt:ntp CT notrack