Generated: 2025-03-23T00:00:00Z -- 2025-03-23T05:43:03Z
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:
66831 of 67983 (98.31%) responded to a EDNS version 0 query
66798 of 67983 (98.26%) responded to a EDNS unknown option
66799 of 67983 (98.26%) responded to a EDNS unknown flags
66725 of 67983 (98.15%) responded to a EDNS version 1 query
66713 of 67983 (98.13%) responded to a EDNS unknown version and option
66148 of 67983 (97.30%) of nameservers support EDNS
3581 of 66148 (5.41%) EDNS capable servers are all ok
63796 of 66148 (96.44%) EDNS capable servers support unknown EDNS versions
65325 of 66148 (98.76%) EDNS capable servers support unknown EDNS options
65449 of 66148 (98.94%) EDNS capable servers support unknown EDNS flags
63581 of 66148 (96.12%) EDNS capable servers support unknown EDNS version and options
65656 of 66148 (99.26%) EDNS capable servers support DO=1
29184 of 66148 (44.12%) EDNS capable servers return a NSID option
23656 of 66148 (35.76%) EDNS capable servers return a EXPIRE option
38264 of 66148 (57.85%) EDNS capable servers return a SUBNET option
22088 of 66148 (33.39%) EDNS capable servers return a Server EDNS COOKIE option
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