🛡️ 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

1,183,573 working delegations with resolvable nameservers (lame excluded)
Every nameserver is on…DomainsShareWhy it matters
A single nameserver host1450.01%Any outage or mistake on that host takes the domain offline; RFC 1034 asks for at least two.
A single nameserver address1,3060.11%Several NS names, but they all resolve to one IP, so they are really one server.
One IPv4 /24 and no IPv610,6800.90%All nameservers share one network: a routing problem there takes them all down.
One autonomous system757,94464.0%Common and usually fine with a large provider, but one network outage still takes all nameservers down.
No IPv6 nameserver85,2767.2%IPv6-only resolvers cannot reach the zone.

Click a row to list its domains (computed 2026-10-05 18:29).

📋 One autonomous system

757,944 domains
DomainNameservers and addresses
webbi.dkernest.ns.cloudflare.com 108.162.193.164 AS13335, 172.64.33.164 AS13335, 173.245.59.164 AS13335, 2606:4700:58::adf5:3ba4 AS13335, 2803:f800:50::6ca2:c1a4 AS13335, 2a06:98c1:50::ac40:21a4 AS13335
ligia.ns.cloudflare.com 108.162.194.4 AS13335, 162.159.38.4 AS13335, 172.64.34.4 AS13335, 2606:4700:50::a29f:2604 AS13335, 2803:f800:50::6ca2:c204 AS13335, 2a06:98c1:50::ac40:2204 AS13335
webbilag.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
webbiler.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
webbillet.dkjewel.ns.cloudflare.com 108.162.194.171 AS13335, 162.159.38.171 AS13335, 172.64.34.171 AS13335, 2606:4700:50::a29f:26ab AS13335, 2803:f800:50::6ca2:c2ab AS13335, 2a06:98c1:50::ac40:22ab AS13335
wells.ns.cloudflare.com 108.162.195.125 AS13335, 162.159.44.125 AS13335, 172.64.35.125 AS13335, 2606:4700:58::a29f:2c7d AS13335, 2803:f800:50::6ca2:c37d AS13335, 2a06:98c1:50::ac40:237d AS13335
webbird.dkns1.openprovider.nl 162.159.26.10 AS13335, 2400:cb00:2049:1::a29f:1a0a AS13335
ns2.openprovider.be 162.159.27.96 AS13335, 2400:cb00:2049:1::a29f:1b60 AS13335
ns3.openprovider.eu 162.159.48.89 AS13335, 2400:cb00:2049:1::a29f:3059 AS13335
webbit.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
webbix.dkns1.nordicway.dk 2a01:4f8:1c1a:a1e7::1 AS24940, 91.98.140.195 AS24940
ns2.nordicway.dk 2a01:4f8:c012:4db6::1 AS24940, 49.13.80.249 AS24940
ns3.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
webbiz-it.dkoswald.ns.cloudflare.com 108.162.193.218 AS13335, 172.64.33.218 AS13335, 173.245.59.218 AS13335, 2606:4700:58::adf5:3bda AS13335, 2803:f800:50::6ca2:c1da AS13335, 2a06:98c1:50::ac40:21da AS13335
rafe.ns.cloudflare.com 108.162.192.216 AS13335, 172.64.32.216 AS13335, 173.245.58.216 AS13335, 2606:4700:50::adf5:3ad8 AS13335, 2803:f800:50::6ca2:c0d8 AS13335, 2a06:98c1:50::ac40:20d8 AS13335
webbiz.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
webbizz.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
webblandet.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
webblanket.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
webbler.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
webblokhus.dkns6.wixdns.net 216.239.32.100 AS15169
ns7.wixdns.net 216.239.34.100 AS15169
webbly.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
webbmail.dkns-210-b.gandi.net 2001:4b98:aaab::d3 AS209453, 213.167.230.211 AS209453
ns-246-c.gandi.net 217.70.187.247 AS209453, 2604:3400:aaac::f7 AS209453
ns-249-a.gandi.net 173.246.100.250 AS209453, 2001:4b98:aaaa::fa AS209453
webbnet.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
webbnov.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
webboden.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
webbog.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
webbogfoering.dkns1.eurodns.com 199.167.66.107 AS23393, 2610:1c8:b002::107 AS23393
ns2.eurodns.com 104.37.178.107 AS23393, 2610:1c8:b001::107 AS23393
ns3.eurodns.com 199.167.66.108 AS23393, 2610:1c8:b002::108 AS23393
ns4.eurodns.com 104.37.178.108 AS23393, 2610:1c8:b001::108 AS23393
webbogføring.dkns1.eurodns.com 199.167.66.107 AS23393, 2610:1c8:b002::107 AS23393
ns2.eurodns.com 104.37.178.107 AS23393, 2610:1c8:b001::107 AS23393
ns3.eurodns.com 199.167.66.108 AS23393, 2610:1c8:b002::108 AS23393
ns4.eurodns.com 104.37.178.108 AS23393, 2610:1c8:b001::108 AS23393
webbojo.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
webbolig.dkdimitris.ns.cloudflare.com 108.162.195.6 AS13335, 162.159.44.6 AS13335, 172.64.35.6 AS13335, 2606:4700:58::a29f:2c06 AS13335, 2803:f800:50::6ca2:c306 AS13335, 2a06:98c1:50::ac40:2306 AS13335
dorthy.ns.cloudflare.com 108.162.192.249 AS13335, 172.64.32.249 AS13335, 173.245.58.249 AS13335, 2606:4700:50::adf5:3af9 AS13335, 2803:f800:50::6ca2:c0f9 AS13335, 2a06:98c1:50::ac40:20f9 AS13335
webbomb.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
webbond.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
webbontheweb.dkns1.nordicnumber.com 91.198.138.46 AS51167
ns2.nordicnumber.com 91.198.138.47 AS51167
ns3.nordicnumber.com 213.136.93.70 AS51167
webbook.dkjewel.ns.cloudflare.com 108.162.194.171 AS13335, 162.159.38.171 AS13335, 172.64.34.171 AS13335, 2606:4700:50::a29f:26ab AS13335, 2803:f800:50::6ca2:c2ab AS13335, 2a06:98c1:50::ac40:22ab AS13335
wells.ns.cloudflare.com 108.162.195.125 AS13335, 162.159.44.125 AS13335, 172.64.35.125 AS13335, 2606:4700:58::a29f:2c7d AS13335, 2803:f800:50::6ca2:c37d AS13335, 2a06:98c1:50::ac40:237d AS13335
webbooking.dkcarioca.ns.cloudflare.com 108.162.194.20 AS13335, 162.159.38.20 AS13335, 172.64.34.20 AS13335, 2606:4700:50::a29f:2614 AS13335, 2803:f800:50::6ca2:c214 AS13335, 2a06:98c1:50::ac40:2214 AS13335
roman.ns.cloudflare.com 108.162.195.103 AS13335, 162.159.44.103 AS13335, 172.64.35.103 AS13335, 2606:4700:58::a29f:2c67 AS13335, 2803:f800:50::6ca2:c367 AS13335, 2a06:98c1:50::ac40:2367 AS13335
webbookwriter.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
webboost.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
webborger.dkns-auth03.kmd.dk 131.165.64.5 AS6834
ns-auth04.kmd.dk 131.165.4.5 AS6834
webboss.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
webbot.dkaliza.ns.cloudflare.com 108.162.194.55 AS13335, 162.159.38.55 AS13335, 172.64.34.55 AS13335, 2606:4700:50::a29f:2637 AS13335, 2803:f800:50::6ca2:c237 AS13335, 2a06:98c1:50::ac40:2237 AS13335
pranab.ns.cloudflare.com 108.162.195.199 AS13335, 162.159.44.199 AS13335, 172.64.35.199 AS13335, 2606:4700:58::a29f:2cc7 AS13335, 2803:f800:50::6ca2:c3c7 AS13335, 2a06:98c1:50::ac40:23c7 AS13335
webbovbjerg.dkns1.mysecurecloudhost.com 13.248.158.180 AS16509
ns2.mysecurecloudhost.com 75.2.118.134 AS16509
ns3.mysecurecloudhost.com 76.223.26.245 AS16509
ns4.mysecurecloudhost.com 99.83.147.209 AS16509
webbrev.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
webbridge.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
webbro.dkns1.webro.dk 185.25.141.12 AS48854, 2a02:2339:4006:108::123 AS48854
ns2.webro.dk 2a02:2339:1:10f::123:123 AS48854, 91.197.248.75 AS48854
webbrochure.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
webbroker.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
webbryggeriet.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
webbuddy.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
webbuild.dkns1.openprovider.nl 162.159.26.10 AS13335, 2400:cb00:2049:1::a29f:1a0a AS13335
ns2.openprovider.be 162.159.27.96 AS13335, 2400:cb00:2049:1::a29f:1b60 AS13335
ns3.openprovider.eu 162.159.48.89 AS13335, 2400:cb00:2049:1::a29f:3059 AS13335
webbuilder.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
webbuilders.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
webbunker.dkgalilea.ns.cloudflare.com 108.162.194.233 AS13335, 162.159.38.233 AS13335, 172.64.34.233 AS13335, 2606:4700:50::a29f:26e9 AS13335, 2803:f800:50::6ca2:c2e9 AS13335, 2a06:98c1:50::ac40:22e9 AS13335
sri.ns.cloudflare.com 108.162.193.234 AS13335, 172.64.33.234 AS13335, 173.245.59.234 AS13335, 2606:4700:58::adf5:3bea AS13335, 2803:f800:50::6ca2:c1ea AS13335, 2a06:98c1:50::ac40:21ea AS13335
webbureau-kobenhavn.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
webbureau-koebenhavn.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
webbureau-kolding.dkns1.cloud-aced59.managed-vps.net 78.128.8.146 AS57344
ns2.cloud-aced59.managed-vps.net 78.128.8.146 AS57344
webbureau-københavn.dkns1.podi.dk 185.25.141.12 AS48854, 2a02:2339:4006:108::123 AS48854
ns2.podi.dk 2a02:2339:1:10f::123:123 AS48854, 91.197.248.75 AS48854
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