Seems like these IPs not responding to ping is not unusual, as per https://www.reddit.com/r/sysadmin/comments/11syv2e/google_dns_8888_dropping_pings_like_crazy_today/

"Google has stated multiple times before as has Level3/CenturyLink/Lumen that 4.2.2.1 and 8.8.8.8 should not be used for ping checks and they will drop packets when under load or if they notice too much activity from a single IP"

-- Dan

On Sun, Jan 12, 2025 at 11:03 PM Mel Beckman <mel@beckman.org> wrote:

Still not pinging from Frontier, Lumen, AT&T, or Verizon networks

 -mel

On Jan 12, 2025, at 4:13 PM, Jerry Cloe <jerry@jtcloe.net> wrote:



O:\>ping 4.2.2.1

 

Pinging 4.2.2.1 with 32 bytes of data:

Reply from 4.2.2.1: bytes=32 time=36ms TTL=56

Reply from 4.2.2.1: bytes=32 time=44ms TTL=56

Reply from 4.2.2.1: bytes=32 time=36ms TTL=56

Reply from 4.2.2.1: bytes=32 time=38ms TTL=56

 

Ping statistics for 4.2.2.1:

    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),

Approximate round trip times in milli-seconds:

    Minimum = 36ms, Maximum = 44ms, Average = 38ms

 

Same for 4.2.2.2

 

-----Original message-----
From: Mel Beckman <mel@beckman.org>
Sent: Sun 01-12-2025 06:07 pm
Subject: Level3 4.2.2.1 and 4.2.2.2 not responding to pings, DNS queries work
To: nanog@nanog.org;
I noticed that Level3 open DNS 4.2.2.1 and 4.2.2.2 stopped responding to ping today. They are responding to DNS queries however.

Does anyone know if this filtering is going to be permanent?

-mel beckman