🛡️ 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

1,186,223 working delegations with resolvable nameservers (lame excluded)
Every nameserver is on…DomainsShareWhy it matters
A single nameserver host1500.01%Any outage or mistake on that host takes the domain offline; RFC 1034 asks for at least two.
A single nameserver address1,3100.11%Several NS names, but they all resolve to one IP, so they are really one server.
One IPv4 /24 and no IPv610,8040.91%All nameservers share one network: a routing problem there takes them all down.
One autonomous system757,13763.8%Common and usually fine with a large provider, but one network outage still takes all nameservers down.
No IPv6 nameserver85,9357.2%IPv6-only resolvers cannot reach the zone.

Click a row to list its domains (computed 2026-09-30 19:36).

📋 One autonomous system

757,137 domains
DomainNameservers and addresses
ørstedskolen.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
ørstedsol.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
ørstedtand.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
ørstedtandklinik.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
ørstedtelte.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
ørstedtelthaller.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
ørstedølbar.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
ørsø.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
ørteby.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
ørting.dkns-1207.awsdns-22.org 205.251.196.183 AS16509, 2600:9000:5304:b700::1 AS16509
ns-1848.awsdns-39.co.uk 205.251.199.56 AS16509, 2600:9000:5307:3800::1 AS16509
ns-502.awsdns-62.com 205.251.193.246 AS16509, 2600:9000:5301:f600::1 AS16509
ns-692.awsdns-22.net 205.251.194.180 AS16509, 2600:9000:5302:b400::1 AS16509
ørtingposten.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
ørtoft.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
ørum-borger.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
ørum-multiservice.dkns1.dns-parking.com 162.159.24.201 AS13335, 2400:cb00:2049:1::a29f:18c9 AS13335
ns2.dns-parking.com 162.159.25.42 AS13335, 2400:cb00:2049:1::a29f:192a AS13335
ørum-murerforretning.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
ørum-savværk.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
ørum.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
ørumandersen.dkalexandra.ns.cloudflare.com 108.162.194.30 AS13335, 162.159.38.30 AS13335, 172.64.34.30 AS13335, 2606:4700:50::a29f:261e AS13335, 2803:f800:50::6ca2:c21e AS13335, 2a06:98c1:50::ac40:221e AS13335
leonard.ns.cloudflare.com 108.162.195.54 AS13335, 162.159.44.54 AS13335, 172.64.35.54 AS13335, 2606:4700:58::a29f:2c36 AS13335, 2803:f800:50::6ca2:c336 AS13335, 2a06:98c1:50::ac40:2336 AS13335
ørumborger.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
ørumforsamlingshus.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
ørumfys.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
ørumgård.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
ørumkirke.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
ørumlanparty.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
ørumnet.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
ørumsavværk.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
ørumvammendyrlæge.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
ørving.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
ns3.dandomain.dk 91.197.248.66 AS48854
ørådet.dkasa.ns.cloudflare.com 108.162.192.246 AS13335, 172.64.32.246 AS13335, 173.245.58.246 AS13335, 2606:4700:50::adf5:3af6 AS13335, 2803:f800:50::6ca2:c0f6 AS13335, 2a06:98c1:50::ac40:20f6 AS13335
lars.ns.cloudflare.com 108.162.193.195 AS13335, 172.64.33.195 AS13335, 173.245.59.195 AS13335, 2606:4700:58::adf5:3bc3 AS13335, 2803:f800:50::6ca2:c1c3 AS13335, 2a06:98c1:50::ac40:21c3 AS13335
øs.dkns6.sitnet.dk 107.162.234.197 AS55002, 2604:e180:1071::3:1 AS55002
ns7.sitnet.dk 107.162.176.221 AS55002, 2604:e180:1071::ffff:6ba2:b0dd AS55002
øsand.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
øsauna.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
øsb.dkmeilani.ns.cloudflare.com 108.162.194.196 AS13335, 162.159.38.196 AS13335, 172.64.34.196 AS13335, 2606:4700:50::a29f:26c4 AS13335, 2803:f800:50::6ca2:c2c4 AS13335, 2a06:98c1:50::ac40:22c4 AS13335
olof.ns.cloudflare.com 108.162.195.51 AS13335, 162.159.44.51 AS13335, 172.64.35.51 AS13335, 2606:4700:58::a29f:2c33 AS13335, 2803:f800:50::6ca2:c333 AS13335, 2a06:98c1:50::ac40:2333 AS13335
øsbymarked.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
øsbyspejder.dkns1.mono.net 185.58.212.1 AS201595
ns2.mono.net 185.130.160.1 AS201595
ns3.mono.net 185.130.160.2 AS201595
ns4.mono.net 185.58.212.2 AS201595
øse.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
øservice.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
øsg.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
øsgfragt.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
øsk.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
øsløs.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
øsløskirke.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
øsløssogn.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
øsløstømrerfirma.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
øspecialiteter.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
øss.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
øst-ark.dkannabel.ns.cloudflare.com 108.162.194.207 AS13335, 162.159.38.207 AS13335, 172.64.34.207 AS13335, 2606:4700:50::a29f:26cf AS13335, 2803:f800:50::6ca2:c2cf AS13335, 2a06:98c1:50::ac40:22cf AS13335
coen.ns.cloudflare.com 108.162.195.151 AS13335, 162.159.44.151 AS13335, 172.64.35.151 AS13335, 2606:4700:58::a29f:2c97 AS13335, 2803:f800:50::6ca2:c397 AS13335, 2a06:98c1:50::ac40:2397 AS13335
øst.dked.ns.cloudflare.com 108.162.193.111 AS13335, 172.64.33.111 AS13335, 173.245.59.111 AS13335, 2606:4700:58::adf5:3b6f AS13335, 2803:f800:50::6ca2:c16f AS13335, 2a06:98c1:50::ac40:216f AS13335
jillian.ns.cloudflare.com 108.162.194.44 AS13335, 162.159.38.44 AS13335, 172.64.34.44 AS13335, 2606:4700:50::a29f:262c AS13335, 2803:f800:50::6ca2:c22c AS13335, 2a06:98c1:50::ac40:222c AS13335
østbanehus.dkns1.abovedomains.com 103.224.182.77 AS133618, 103.224.182.85 AS133618, 103.224.182.9 AS133618, 103.224.212.9 AS133618
ns2.abovedomains.com 103.224.182.10 AS133618, 103.224.212.10 AS133618, 103.224.212.51 AS133618, 103.224.212.53 AS133618
østberg.dkns1.azehosting.net 2a01:4f8:13b:3146::1 AS24940, 94.130.138.185 AS24940
ns2.azehosting.net 2a01:4f8:c17:5f0a::2 AS24940, 88.99.15.5 AS24940
ns3.azehosting.net 2a01:4f8:c17:6a6e::2 AS24940, 88.99.39.181 AS24940
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