First thought was ISP intermittent packet loss, but
Ping is unaffected
no packet loss or jitter
Speedtests of any kind always return when problem is occurring / when problem is not occurring
Suggests otherwise. My second thought was DNS crashing, but
DNS seems irrelevant
You already got it covered.
Some websites like Facebook and Google work
VOIP does not seem to be affected
Really weird situation! Try using wireshark to listen on the interface and observe what’s happening. Are packets going out but none returning? Are they returning with errors? Retransmissions? Are some destinations fine but others get no reply?
Could you geographically locate the IPs that work vs. the IPs that don’t? My next suspicion is that there is some upstream backbone link that cuts out, so stuff with local CDNs like facebook continue to work, but a lemmy server on another continent is unreachable. Try traceroute.
First thought was ISP intermittent packet loss, but
Suggests otherwise. My second thought was DNS crashing, but
You already got it covered.
Really weird situation! Try using wireshark to listen on the interface and observe what’s happening. Are packets going out but none returning? Are they returning with errors? Retransmissions? Are some destinations fine but others get no reply?
Could you geographically locate the IPs that work vs. the IPs that don’t? My next suspicion is that there is some upstream backbone link that cuts out, so stuff with local CDNs like facebook continue to work, but a lemmy server on another continent is unreachable. Try traceroute.