🛡️ 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

1,183,327 working delegations with resolvable nameservers (lame excluded)
Every nameserver is on…DomainsShareWhy it matters
A single nameserver host1530.01%Any outage or mistake on that host takes the domain offline; RFC 1034 asks for at least two.
A single nameserver address1,3090.11%Several NS names, but they all resolve to one IP, so they are really one server.
One IPv4 /24 and no IPv610,6870.90%All nameservers share one network: a routing problem there takes them all down.
One autonomous system757,76764.0%Common and usually fine with a large provider, but one network outage still takes all nameservers down.
No IPv6 nameserver85,3247.2%IPv6-only resolvers cannot reach the zone.

Click a row to list its domains (computed 2026-10-03 16:39).

📋 One autonomous system

757,767 domains
DomainNameservers and addresses
aalborgfilmklub.dktan-dns01.tang.ind.yacn.dk 193.88.11.6 AS3292
tan-dns02.tang.ind.yacn.dk 193.88.11.7 AS3292
aalborgfirmagaven.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
aalborgfirmagaver.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
aalborgflagfabrik.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
aalborgfliserens.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
aalborgflyers.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
aalborgflyttefirma.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
aalborgflytteforretning.dkfrida.ns.cloudflare.com 108.162.194.137 AS13335, 162.159.38.137 AS13335, 172.64.34.137 AS13335, 2606:4700:50::a29f:2689 AS13335, 2803:f800:50::6ca2:c289 AS13335, 2a06:98c1:50::ac40:2289 AS13335
grant.ns.cloudflare.com 108.162.195.130 AS13335, 162.159.44.130 AS13335, 172.64.35.130 AS13335, 2606:4700:58::a29f:2c82 AS13335, 2803:f800:50::6ca2:c382 AS13335, 2a06:98c1:50::ac40:2382 AS13335
aalborgfodboldgolf.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
aalborgfodtennis.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
aalborgfodterapeut.dkns1.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
aalborgfoerstehjaelp.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
aalborgfokus.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
aalborgfoodtruck.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
aalborgfoodtrucks.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
aalborgforsikring.dkns.scannet2.dk 185.25.141.9 AS48854, 2a02:2339:4006:10d::4171:4171 AS48854
ns2.scannet2.dk 2a02:2339:1:112:0:5:1:b11 AS48854, 91.197.248.72 AS48854
aalborgforsyning.dkns.scannet2.dk 185.25.141.9 AS48854, 2a02:2339:4006:10d::4171:4171 AS48854
ns2.scannet2.dk 2a02:2339:1:112:0:5:1:b11 AS48854, 91.197.248.72 AS48854
aalborgforsyninq.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
aalborgfotoklub.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
aalborgfriskole.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
aalborgfritid.dkns.scannet2.dk 185.25.141.9 AS48854, 2a02:2339:4006:10d::4171:4171 AS48854
ns2.scannet2.dk 2a02:2339:1:112:0:5:1:b11 AS48854, 91.197.248.72 AS48854
aalborgfrivilligcenter.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
aalborgfugeservice.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
aalborgfugeteknik.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
aalborgfutsal.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
aalborgfutsalklub.dkns1.parkingcrew.net 13.248.158.159 AS16509
ns2.parkingcrew.net 76.223.21.9 AS16509
aalborgfys.dkanderson.ns.cloudflare.com 108.162.195.177 AS13335, 162.159.44.177 AS13335, 172.64.35.177 AS13335, 2606:4700:58::a29f:2cb1 AS13335, 2803:f800:50::6ca2:c3b1 AS13335, 2a06:98c1:50::ac40:23b1 AS13335
stephane.ns.cloudflare.com 108.162.194.112 AS13335, 162.159.38.112 AS13335, 172.64.34.112 AS13335, 2606:4700:50::a29f:2670 AS13335, 2803:f800:50::6ca2:c270 AS13335, 2a06:98c1:50::ac40:2270 AS13335
aalborgfysio.dkanderson.ns.cloudflare.com 108.162.195.177 AS13335, 162.159.44.177 AS13335, 172.64.35.177 AS13335, 2606:4700:58::a29f:2cb1 AS13335, 2803:f800:50::6ca2:c3b1 AS13335, 2a06:98c1:50::ac40:23b1 AS13335
stephane.ns.cloudflare.com 108.162.194.112 AS13335, 162.159.38.112 AS13335, 172.64.34.112 AS13335, 2606:4700:50::a29f:2670 AS13335, 2803:f800:50::6ca2:c270 AS13335, 2a06:98c1:50::ac40:2270 AS13335
aalborgfysioterapeut.dkanderson.ns.cloudflare.com 108.162.195.177 AS13335, 162.159.44.177 AS13335, 172.64.35.177 AS13335, 2606:4700:58::a29f:2cb1 AS13335, 2803:f800:50::6ca2:c3b1 AS13335, 2a06:98c1:50::ac40:23b1 AS13335
stephane.ns.cloudflare.com 108.162.194.112 AS13335, 162.159.38.112 AS13335, 172.64.34.112 AS13335, 2606:4700:50::a29f:2670 AS13335, 2803:f800:50::6ca2:c270 AS13335, 2a06:98c1:50::ac40:2270 AS13335
aalborgfysioterapeuten.dkanderson.ns.cloudflare.com 108.162.195.177 AS13335, 162.159.44.177 AS13335, 172.64.35.177 AS13335, 2606:4700:58::a29f:2cb1 AS13335, 2803:f800:50::6ca2:c3b1 AS13335, 2a06:98c1:50::ac40:23b1 AS13335
stephane.ns.cloudflare.com 108.162.194.112 AS13335, 162.159.38.112 AS13335, 172.64.34.112 AS13335, 2606:4700:50::a29f:2670 AS13335, 2803:f800:50::6ca2:c270 AS13335, 2a06:98c1:50::ac40:2270 AS13335
aalborgfysioterapeuter.dkanderson.ns.cloudflare.com 108.162.195.177 AS13335, 162.159.44.177 AS13335, 172.64.35.177 AS13335, 2606:4700:58::a29f:2cb1 AS13335, 2803:f800:50::6ca2:c3b1 AS13335, 2a06:98c1:50::ac40:23b1 AS13335
stephane.ns.cloudflare.com 108.162.194.112 AS13335, 162.159.38.112 AS13335, 172.64.34.112 AS13335, 2606:4700:50::a29f:2670 AS13335, 2803:f800:50::6ca2:c270 AS13335, 2a06:98c1:50::ac40:2270 AS13335
aalborgfysioterapeuterne.dkanderson.ns.cloudflare.com 108.162.195.177 AS13335, 162.159.44.177 AS13335, 172.64.35.177 AS13335, 2606:4700:58::a29f:2cb1 AS13335, 2803:f800:50::6ca2:c3b1 AS13335, 2a06:98c1:50::ac40:23b1 AS13335
stephane.ns.cloudflare.com 108.162.194.112 AS13335, 162.159.38.112 AS13335, 172.64.34.112 AS13335, 2606:4700:50::a29f:2670 AS13335, 2803:f800:50::6ca2:c270 AS13335, 2a06:98c1:50::ac40:2270 AS13335
aalborgfysioterapi.dkanderson.ns.cloudflare.com 108.162.195.177 AS13335, 162.159.44.177 AS13335, 172.64.35.177 AS13335, 2606:4700:58::a29f:2cb1 AS13335, 2803:f800:50::6ca2:c3b1 AS13335, 2a06:98c1:50::ac40:23b1 AS13335
stephane.ns.cloudflare.com 108.162.194.112 AS13335, 162.159.38.112 AS13335, 172.64.34.112 AS13335, 2606:4700:50::a29f:2670 AS13335, 2803:f800:50::6ca2:c270 AS13335, 2a06:98c1:50::ac40:2270 AS13335
aalborgførstehjælp.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
aalborggardiner.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
aalborggardinerogmarkiser.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
aalborggartner.dkben.ns.cloudflare.com 108.162.193.103 AS13335, 172.64.33.103 AS13335, 173.245.59.103 AS13335, 2606:4700:58::adf5:3b67 AS13335, 2803:f800:50::6ca2:c167 AS13335, 2a06:98c1:50::ac40:2167 AS13335
sharon.ns.cloudflare.com 108.162.192.221 AS13335, 172.64.32.221 AS13335, 173.245.58.221 AS13335, 2606:4700:50::adf5:3add AS13335, 2803:f800:50::6ca2:c0dd AS13335, 2a06:98c1:50::ac40:20dd AS13335
aalborggave.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
aalborggavekortet.dkns1178.hexonet.net 194.50.187.178 AS1921
ns2188.hexonet.net 194.0.182.188 AS1921
ns3180.hexonet.net 193.227.117.180 AS1921
aalborggaven.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
aalborggaver.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
aalborggenbrug.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
aalborgglarmester.dkns1.dnsserver.dk 185.25.141.12 AS48854, 2a02:2339:4006:108::123 AS48854
ns2.dnsserver.dk 2a02:2339:1:10f::123:123 AS48854, 91.197.248.75 AS48854
aalborgglarmesterforretning.dkns1.dnsserver.dk 185.25.141.12 AS48854, 2a02:2339:4006:108::123 AS48854
ns2.dnsserver.dk 2a02:2339:1:10f::123:123 AS48854, 91.197.248.75 AS48854
aalborgglarmestertømrer.dkns1.dnsserver.dk 185.25.141.12 AS48854, 2a02:2339:4006:108::123 AS48854
ns2.dnsserver.dk 2a02:2339:1:10f::123:123 AS48854, 91.197.248.75 AS48854
aalborggolfsimulator.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
aalborggrafisk.dkns61.domaincontrol.com 2603:5:2153::20 AS44273, 97.74.101.32 AS44273
ns62.domaincontrol.com 173.201.69.32 AS44273, 2603:5:2253::20 AS44273
aalborggrandprix.dkns3.webhot.dk 178.72.21.249 AS3342
ns4.webhot.dk 178.72.21.250 AS3342
aalborggrillfestival.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
aalborggrunde.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
dhd.dk [/] search Domains, Hosts & DNS — .dk zone