Generated: 2020-11-22T00:00:05Z -- 2020-11-23T11:24:17Z
The following report was generated automatically.
Packet loss and network issues may have introduced false positives.
Please verify the results before taking action.
You can report issues with this report to: marka@isc.org
Most recursive resolvers now support EDNS. Lack of EDNS support in authoritative servers results in additional queries being made as the recursive servers need to retry with plain DNS and results in slower DNS resolution.
Not answering EDNS queries is particularly bad as that is indistingishable from packet loss.
Incorrect EDNS behaviour when presented with unknown EDNS versions and EDNS options can result in DNS resolution failures and/or DNSSEC validation failures.
Failure to run fully EDNS compliant nameservers will make it hard to deploy developments like DNS COOKIES which provides mitigation against DNS amplification attacks, off path spoofing resistance, RRL advoidance and excessive resource usage.
ok - test passed.
badvers - BADVERS returned.
badversion - expected EDNS version not found.
echoed - EDNS option echoed back.
formerr - FORMERR returned.
mbz - EDNS flags echoed back.
nodo - EDNS DO flag not echoed.
noopt - OPT record not found when expected.
nosoa - SOA not found when expected.
notimp - NOTIMP returned.
refused - REFUSED returned.
servfail - SERVFAIL returned.
soa - SOA found when not expected.
status - expected status code not found.
toobig - UDP response bigger that advertised buffer size.
version - expected EDNS version not found.
reset - TCP connection reset.
timeout - lookup timed out.
Of servers that responded at all:
177255 of 179438 (98.78%) responded to a EDNS version 0 query
177205 of 179438 (98.76%) responded to a EDNS unknown option
177097 of 179438 (98.70%) responded to a EDNS unknown flags
176565 of 179438 (98.40%) responded to a EDNS version 1 query
176549 of 179438 (98.39%) responded to a EDNS unknown version and option
174526 of 179438 (97.26%) of nameservers support EDNS
4835 of 174526 (2.77%) EDNS capable servers are all ok
168879 of 174526 (96.76%) EDNS capable servers support unknown EDNS versions
168183 of 174526 (96.37%) EDNS capable servers support unknown EDNS options
173253 of 174526 (99.27%) EDNS capable servers support unknown EDNS flags
163720 of 174526 (93.81%) EDNS capable servers support unknown EDNS version and options
173986 of 174526 (99.69%) EDNS capable servers support DO=1
39432 of 174526 (22.59%) EDNS capable servers return a NSID option
60684 of 174526 (34.77%) EDNS capable servers return a EXPIRE option
66370 of 174526 (38.03%) EDNS capable servers return a SUBNET option
52484 of 174526 (30.07%) EDNS capable servers return a Server EDNS COOKIE option
© 2020 Internet Systems Consortium