🛡️ Nameserver Resilience

Domains whose DNS hangs on a single nameserver, address, network or AS · all insights

DNS should never hang on one server. This page counts the .dk domains whose nameservers share a single host, address, network or autonomous system, the single points of failure that turn one outage into a dead domain. Data comes from our own scanners, which re-resolve every .dk domain in the zone roughly once a week.

🛡️ Single points of failure

1,183,657 working delegations with resolvable nameservers (lame excluded)
Every nameserver is on…DomainsShareWhy it matters
A single nameserver host1490.01%Any outage or mistake on that host takes the domain offline; RFC 1034 asks for at least two.
A single nameserver address1,3070.11%Several NS names, but they all resolve to one IP, so they are really one server.
One IPv4 /24 and no IPv610,6840.90%All nameservers share one network: a routing problem there takes them all down.
One autonomous system758,17064.1%Common and usually fine with a large provider, but one network outage still takes all nameservers down.
No IPv6 nameserver85,3597.2%IPv6-only resolvers cannot reach the zone.

Click a row to list its domains (computed 2026-10-04 17:29).

📋 One autonomous system

758,170 domains
DomainNameservers and addresses
abcbolte.dkdns1.pro.dk 37.140.219.20 AS31027
dns2.pro.dk 37.140.219.21 AS31027
abcbook.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
ns4.simply.com 91.197.248.80 AS48854
abcbooks.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
ns4.simply.com 91.197.248.80 AS48854
abcborydning.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
abcbrudekjoler.dkns1.curanet.dk 185.25.141.12 AS48854, 2a02:2339:4006:108::123 AS48854
ns2.curanet.dk 2a02:2339:1:10f::123:123 AS48854, 91.197.248.75 AS48854
abcbusiness.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
abcbyg.dkns1.curanet.dk 185.25.141.12 AS48854, 2a02:2339:4006:108::123 AS48854
ns2.curanet.dk 2a02:2339:1:10f::123:123 AS48854, 91.197.248.75 AS48854
abcbyggeplads.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
abcbyggeplads2.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
abccapital.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
abcchat.dkns1.emailverification.info 54.38.220.85 AS16276
ns2.emailverification.info 94.23.162.163 AS16276
abccomputer.dkaustin.ns.cloudflare.com 108.162.193.70 AS13335, 172.64.33.70 AS13335, 173.245.59.70 AS13335, 2606:4700:58::adf5:3b46 AS13335, 2803:f800:50::6ca2:c146 AS13335, 2a06:98c1:50::ac40:2146 AS13335
izabella.ns.cloudflare.com 108.162.194.46 AS13335, 162.159.38.46 AS13335, 172.64.34.46 AS13335, 2606:4700:50::a29f:262e AS13335, 2803:f800:50::6ca2:c22e AS13335, 2a06:98c1:50::ac40:222e AS13335
abcconsult.dkns.dandomain.dk 185.25.141.3 AS48854, 2a02:2339:4006:109::dd AS48854
ns2.dandomain.dk 2a02:2339:1:108::dd:dd AS48854, 91.197.248.66 AS48854
abcd-asaa.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
ns4.simply.com 91.197.248.80 AS48854
abcd-bolig.dkelaine.ns.cloudflare.com 108.162.192.152 AS13335, 172.64.32.152 AS13335, 173.245.58.152 AS13335, 2606:4700:50::adf5:3a98 AS13335, 2803:f800:50::6ca2:c098 AS13335, 2a06:98c1:50::ac40:2098 AS13335
michael.ns.cloudflare.com 108.162.195.12 AS13335, 162.159.44.12 AS13335, 172.64.35.12 AS13335, 2606:4700:58::a29f:2c0c AS13335, 2803:f800:50::6ca2:c30c AS13335, 2a06:98c1:50::ac40:230c AS13335
abcd.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
abcdefghijklmnopqrstuvwxyz.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
ns4.simply.com 91.197.248.80 AS48854
abcdefghijklmnopqrstuvwxyzæøå.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
ns4.simply.com 91.197.248.80 AS48854
abcdemens.dkns.dandomain.dk 185.25.141.3 AS48854, 2a02:2339:4006:109::dd AS48854
ns2.dandomain.dk 2a02:2339:1:108::dd:dd AS48854, 91.197.248.66 AS48854
abcdgrillz.dkns10.wixdns.net 216.239.36.100 AS15169
ns11.wixdns.net 216.239.38.100 AS15169
abcdj.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
abcdreng.dkns.dandomain.dk 185.25.141.3 AS48854, 2a02:2339:4006:109::dd AS48854
ns2.dandomain.dk 2a02:2339:1:108::dd:dd AS48854, 91.197.248.66 AS48854
abcdyr.dkblair.ns.cloudflare.com 108.162.194.121 AS13335, 162.159.38.121 AS13335, 172.64.34.121 AS13335, 2606:4700:50::a29f:2679 AS13335, 2803:f800:50::6ca2:c279 AS13335, 2a06:98c1:50::ac40:2279 AS13335
frank.ns.cloudflare.com 108.162.193.166 AS13335, 172.64.33.166 AS13335, 173.245.59.166 AS13335, 2606:4700:58::adf5:3ba6 AS13335, 2803:f800:50::6ca2:c1a6 AS13335, 2a06:98c1:50::ac40:21a6 AS13335
abcedariet.dkns.dandomain.dk 185.25.141.3 AS48854, 2a02:2339:4006:109::dd AS48854
ns2.dandomain.dk 2a02:2339:1:108::dd:dd AS48854, 91.197.248.66 AS48854
abcedo.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
abcejendomme.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
ns4.simply.com 91.197.248.80 AS48854
abcel.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
ns4.simply.com 91.197.248.80 AS48854
abcelservice.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
ns4.simply.com 91.197.248.80 AS48854
abcenter.dkns3.nordicway.dk 2a01:4f8:c2c:d3c0::1 AS24940, 78.47.45.64 AS24940
ns4.nordicway.dk 2a01:4f8:c010:24a2::1 AS24940, 78.47.56.84 AS24940
abcetiketter.dkns.dandomain.dk 185.25.141.3 AS48854, 2a02:2339:4006:109::dd AS48854
ns2.dandomain.dk 2a02:2339:1:108::dd:dd AS48854, 91.197.248.66 AS48854
abcfacader.dkns.dandomain.dk 185.25.141.3 AS48854, 2a02:2339:4006:109::dd AS48854
ns2.dandomain.dk 2a02:2339:1:108::dd:dd AS48854, 91.197.248.66 AS48854
abcfacility.dkbruce.ns.cloudflare.com 108.162.193.77 AS13335, 172.64.33.77 AS13335, 173.245.59.77 AS13335, 2606:4700:58::adf5:3b4d AS13335, 2803:f800:50::6ca2:c14d AS13335, 2a06:98c1:50::ac40:214d AS13335
mia.ns.cloudflare.com 108.162.192.200 AS13335, 172.64.32.200 AS13335, 173.245.58.200 AS13335, 2606:4700:50::adf5:3ac8 AS13335, 2803:f800:50::6ca2:c0c8 AS13335, 2a06:98c1:50::ac40:20c8 AS13335
abcfilm.dkns.wannafind.dk 185.25.141.6 AS48854, 2a02:2339:4006:103:1c:3f6d:daba:dee AS48854
ns2.wannafind.dk 2a02:2339:1:104::daba:daa AS48854, 91.197.248.69 AS48854
abcfinans.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
abcflightacademy.dkns.dandomain.dk 185.25.141.3 AS48854, 2a02:2339:4006:109::dd AS48854
ns2.dandomain.dk 2a02:2339:1:108::dd:dd AS48854, 91.197.248.66 AS48854
abcflyt.dkns1.curanet.dk 185.25.141.12 AS48854, 2a02:2339:4006:108::123 AS48854
ns2.curanet.dk 2a02:2339:1:10f::123:123 AS48854, 91.197.248.75 AS48854
abcflytteforretning.dkns1.gnrx.dk 185.25.141.12 AS48854, 2a02:2339:4006:108::123 AS48854
ns2.gnrx.dk 2a02:2339:1:10f::123:123 AS48854, 91.197.248.75 AS48854
abcfoerstehjaelp.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
abcformentalsundhed.dkian.ns.cloudflare.com 108.162.193.118 AS13335, 172.64.33.118 AS13335, 173.245.59.118 AS13335, 2606:4700:58::adf5:3b76 AS13335, 2803:f800:50::6ca2:c176 AS13335, 2a06:98c1:50::ac40:2176 AS13335
tiffany.ns.cloudflare.com 108.162.194.60 AS13335, 162.159.38.60 AS13335, 172.64.34.60 AS13335, 2606:4700:50::a29f:263c AS13335, 2803:f800:50::6ca2:c23c AS13335, 2a06:98c1:50::ac40:223c AS13335
abcforsikring.dkandronicus.ns.cloudflare.com 108.162.195.113 AS13335, 162.159.44.113 AS13335, 172.64.35.113 AS13335, 2606:4700:58::a29f:2c71 AS13335, 2803:f800:50::6ca2:c371 AS13335, 2a06:98c1:50::ac40:2371 AS13335
hazel.ns.cloudflare.com 108.162.194.157 AS13335, 162.159.38.157 AS13335, 172.64.34.157 AS13335, 2606:4700:50::a29f:269d AS13335, 2803:f800:50::6ca2:c29d AS13335, 2a06:98c1:50::ac40:229d AS13335
abcforstehjaelp.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
abcførstehjælp.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
abcglas.dkns01.leehansenit.net 88.99.120.238 AS24940
ns02.leehansenit.net 94.130.170.39 AS24940
abcgruppen.dkns1.namesystem.se 195.238.76.18 AS42708, 2a02:750:aaaa::1 AS42708
ns2.namesystem.se 195.238.77.18 AS42708, 2a02:750:aaaa::2 AS42708
abcguide.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
abcgulve.dkns1.simply.com 2a02:2339:1:15c::4562:4562 AS48854, 91.197.248.78 AS48854
ns2.simply.com 185.25.141.15 AS48854, 2a02:2339:4006:101::4562:4562 AS48854
ns3.simply.com 91.197.248.79 AS48854
ns4.simply.com 91.197.248.80 AS48854
abcharlottehaven.dkns3.nordicway.dk 2a01:4f8:c2c:d3c0::1 AS24940, 78.47.45.64 AS24940
ns4.nordicway.dk 2a01:4f8:c010:24a2::1 AS24940, 78.47.56.84 AS24940
abchat.dkns1.emailverification.info 54.38.220.85 AS16276
ns2.emailverification.info 94.23.162.163 AS16276
abchild.dkns1.telenor.dk 2001:1580:0:1806::10 AS9158, 212.242.39.142 AS9158
ns2.telenor.dk 2001:1580:0:1206::10 AS9158, 212.242.39.166 AS9158
abchill.dkns.dandomain.dk 185.25.141.3 AS48854, 2a02:2339:4006:109::dd AS48854
ns2.dandomain.dk 2a02:2339:1:108::dd:dd AS48854, 91.197.248.66 AS48854
dhd.dk [/] search Domains, Hosts & DNS — .dk zone