[dns-operations] DNSviz and G-root: EDNS issue?

[Keith Mitchell]

On 10/12/21 11:14 AM, Stephane Bortzmeyer wrote:
> DNSviz currently always flags the root with a warning "./DNSKEY (alg
> 8, id 14748): 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. (192.112.36.4, UDP_-_EDNS0_4096_D_KN)".
> 
> Testing G-root/192.112.36.4 with the RIPE Atlas probes, bit DO and
> bufsize=4096 shows no evidence of a problem (and the answer is well
> below 4096 bytes). It seems it affects only the path between G-root
> and DNSviz.
> 
> Any idea?

This might be a known intermittent IPv6 routing issue with DNSviz, do 
you see this problem for v4 and/or v6 ?

Keith