🛡️ 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

1,183,325 working delegations with resolvable nameservers (lame excluded)
Every nameserver is on…DomainsShareWhy it matters
A single nameserver host1520.01%Any outage or mistake on that host takes the domain offline; RFC 1034 asks for at least two.
A single nameserver address1,3110.11%Several NS names, but they all resolve to one IP, so they are really one server.
One IPv4 /24 and no IPv610,6890.90%All nameservers share one network: a routing problem there takes them all down.
One autonomous system757,85464.0%Common and usually fine with a large provider, but one network outage still takes all nameservers down.
No IPv6 nameserver85,3487.2%IPv6-only resolvers cannot reach the zone.

Click a row to list its domains (computed 2026-10-04 05:03).

📋 One autonomous system

757,854 domains
DomainNameservers and addresses
windk2012.dkabby.ns.cloudflare.com 108.162.192.100 AS13335, 172.64.32.100 AS13335, 173.245.58.100 AS13335, 2606:4700:50::adf5:3a64 AS13335, 2803:f800:50::6ca2:c064 AS13335, 2a06:98c1:50::ac40:2064 AS13335
quinton.ns.cloudflare.com 108.162.195.249 AS13335, 162.159.44.249 AS13335, 172.64.35.249 AS13335, 2606:4700:58::a29f:2cf9 AS13335, 2803:f800:50::6ca2:c3f9 AS13335, 2a06:98c1:50::ac40:23f9 AS13335
windliner.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
windman.dkudns1.cscdns.net 2001:502:f3ff::201 AS12008, 204.74.66.1 AS12008
udns2.cscdns.uk 2001:502:4612::201 AS12008, 204.74.111.1 AS12008
windmanonline.dkudns1.cscdns.net 2001:502:f3ff::201 AS12008, 204.74.66.1 AS12008
udns2.cscdns.uk 2001:502:4612::201 AS12008, 204.74.111.1 AS12008
windme.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
windminds.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
windnielsen.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
windnow.dkns1.variomedia.de 185.95.96.53 AS48519, 2a00:1c3e:96::53 AS48519
ns2.variomedia.de 185.95.98.53 AS48519, 2a00:1c3e:98::53 AS48519
windocg.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
windofchange.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
windofhope.dkiris.ns.cloudflare.com 108.162.192.118 AS13335, 172.64.32.118 AS13335, 173.245.58.118 AS13335, 2606:4700:50::adf5:3a76 AS13335, 2803:f800:50::6ca2:c076 AS13335, 2a06:98c1:50::ac40:2076 AS13335
terin.ns.cloudflare.com 108.162.193.236 AS13335, 172.64.33.236 AS13335, 173.245.59.236 AS13335, 2606:4700:58::adf5:3bec AS13335, 2803:f800:50::6ca2:c1ec AS13335, 2a06:98c1:50::ac40:21ec AS13335
windops.dkrandall.ns.cloudflare.com 108.162.195.235 AS13335, 162.159.44.235 AS13335, 172.64.35.235 AS13335, 2606:4700:58::a29f:2ceb AS13335, 2803:f800:50::6ca2:c3eb AS13335, 2a06:98c1:50::ac40:23eb AS13335
selah.ns.cloudflare.com 108.162.194.21 AS13335, 162.159.38.21 AS13335, 172.64.34.21 AS13335, 2606:4700:50::a29f:2615 AS13335, 2803:f800:50::6ca2:c215 AS13335, 2a06:98c1:50::ac40:2215 AS13335
windos.dkkristin.ns.cloudflare.com 108.162.192.181 AS13335, 172.64.32.181 AS13335, 173.245.58.181 AS13335, 2606:4700:50::adf5:3ab5 AS13335, 2803:f800:50::6ca2:c0b5 AS13335, 2a06:98c1:50::ac40:20b5 AS13335
ricardo.ns.cloudflare.com 108.162.195.211 AS13335, 162.159.44.211 AS13335, 172.64.35.211 AS13335, 2606:4700:58::a29f:2cd3 AS13335, 2803:f800:50::6ca2:c3d3 AS13335, 2a06:98c1:50::ac40:23d3 AS13335
windovation.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
window-company.dkdns1.cscdns.net 156.154.130.100 AS12008, 2610:a1:1022::100 AS12008
dns2.cscdns.net 156.154.131.100 AS12008, 2610:a1:1023::100 AS12008
window.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
marek.ns.cloudflare.com 108.162.193.202 AS13335, 172.64.33.202 AS13335, 173.245.59.202 AS13335, 2606:4700:58::adf5:3bca AS13335, 2803:f800:50::6ca2:c1ca AS13335, 2a06:98c1:50::ac40:21ca AS13335
windowcleaner.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
windowcleanerschool.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
windowcleaning.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
windowcleaningcopenhagen.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
windowcleaningcph.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
windowcollection.dkdns1.cscdns.net 156.154.130.100 AS12008, 2610:a1:1022::100 AS12008
dns2.cscdns.net 156.154.131.100 AS12008, 2610:a1:1023::100 AS12008
windowcompany.dkdns1.cscdns.net 156.154.130.100 AS12008, 2610:a1:1022::100 AS12008
dns2.cscdns.net 156.154.131.100 AS12008, 2610:a1:1023::100 AS12008
windowfood.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
windowfrance.dkns1.linode.com 2600:14c0:6::2 AS21342, 92.123.94.2 AS21342
ns2.linode.com 2600:14c0:6::3 AS21342, 92.123.94.3 AS21342
ns3.linode.com 2600:14c0:7::3 AS21342, 92.123.95.3 AS21342
ns4.linode.com 2600:14c0:7::4 AS21342, 92.123.95.4 AS21342
ns5.linode.com 2600:14c0:7::2 AS21342, 92.123.95.2 AS21342
windowgraphics.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
windowmaster.dkns1.brandshelter.com 193.227.117.9 AS1921, 2a04:2b00:14cc::9 AS1921
ns2.brandshelter.de 194.50.187.11 AS1921, 2a04:2b00:14dd::11 AS1921
ns3.brandshelter.info 194.0.182.12 AS1921, 2a04:2b00:14ee::12 AS1921
ns4.brandshelter.net 193.227.117.10 AS1921, 2a04:2b00:14cc::10 AS1921
ns5.brandshelter.us 194.50.187.14 AS1921, 2a04:2b00:14dd::14 AS1921
windows-box.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
windows-firewall.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
windows.dkdee.ns.cloudflare.com 108.162.192.93 AS13335, 172.64.32.93 AS13335, 173.245.58.93 AS13335, 2606:4700:50::adf5:3a5d AS13335, 2803:f800:50::6ca2:c05d AS13335, 2a06:98c1:50::ac40:205d AS13335
marty.ns.cloudflare.com 108.162.193.204 AS13335, 172.64.33.204 AS13335, 173.245.59.204 AS13335, 2606:4700:58::adf5:3bcc AS13335, 2803:f800:50::6ca2:c1cc AS13335, 2a06:98c1:50::ac40:21cc AS13335
windows10.dkns1-08.azure-dns.com 13.107.236.8 AS8075, 2603:1061:0:700::8 AS8075
ns2-08.azure-dns.net 150.171.21.8 AS8075, 2620:1ec:8ec:700::8 AS8075
ns3-08.azure-dns.org 204.14.183.8 AS8075, 2a01:111:4000:700::8 AS8075
ns4-08.azure-dns.info 208.84.5.8 AS8075, 2620:1ec:bda:700::8 AS8075
windows12.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
windows24.dkns5.kasserver.com 85.13.128.3 AS34788
ns6.kasserver.com 85.13.159.101 AS34788
windows365.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
windows7.dkns1-08.azure-dns.com 13.107.236.8 AS8075, 2603:1061:0:700::8 AS8075
ns2-08.azure-dns.net 150.171.21.8 AS8075, 2620:1ec:8ec:700::8 AS8075
ns3-08.azure-dns.org 204.14.183.8 AS8075, 2a01:111:4000:700::8 AS8075
ns4-08.azure-dns.info 208.84.5.8 AS8075, 2620:1ec:bda:700::8 AS8075
windowsadmin.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
windowsanddoors.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
windowsazure.dkns1-05.azure-dns.com 13.107.236.5 AS8075, 2603:1061:0:700::5 AS8075
ns2-05.azure-dns.net 150.171.21.5 AS8075, 2620:1ec:8ec:700::5 AS8075
ns3-05.azure-dns.org 204.14.183.5 AS8075, 2a01:111:4000:700::5 AS8075
ns4-05.azure-dns.info 208.84.5.5 AS8075, 2620:1ec:bda:700::5 AS8075
windowsbutik.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
windowshotel.dkns51.gullestrupnet.dk 82.165.189.144 AS8560
ns52.gullestrupnet.dk 82.165.203.134
windowsill.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
windowsintune.dkns1-07.azure-dns.com 13.107.236.7 AS8075, 2603:1061:0:700::7 AS8075
ns2-07.azure-dns.net 150.171.21.7 AS8075, 2620:1ec:8ec:700::7 AS8075
ns3-07.azure-dns.org 204.14.183.7 AS8075, 2a01:111:4000:700::7 AS8075
ns4-07.azure-dns.info 208.84.5.7 AS8075, 2620:1ec:bda:700::7 AS8075
windowskonsulent.dkns1.bdm.microsoftonline.com 13.107.236.208 AS8075, 2603:1061:0:700::d0 AS8075
ns2.bdm.microsoftonline.com 150.171.21.208 AS8075, 2620:1ec:8ec:700::d0 AS8075
ns3.bdm.microsoftonline.com 204.14.183.208 AS8075, 2a01:111:4000:700::d0 AS8075
ns4.bdm.microsoftonline.com 208.84.5.208 AS8075, 2620:1ec:bda:700::d0 AS8075
windowslive.dkns1-02.azure-dns.com 13.107.236.2 AS8075, 2603:1061:0:700::2 AS8075
ns2-02.azure-dns.net 150.171.21.2 AS8075, 2620:1ec:8ec:700::2 AS8075
ns3-02.azure-dns.org 204.14.183.2 AS8075, 2a01:111:4000:700::2 AS8075
ns4-02.azure-dns.info 208.84.5.2 AS8075, 2620:1ec:bda:700::2 AS8075
windowsmarketplace.dkns1-02.azure-dns.com 13.107.236.2 AS8075, 2603:1061:0:700::2 AS8075
ns2-02.azure-dns.net 150.171.21.2 AS8075, 2620:1ec:8ec:700::2 AS8075
ns3-02.azure-dns.org 204.14.183.2 AS8075, 2a01:111:4000:700::2 AS8075
ns4-02.azure-dns.info 208.84.5.2 AS8075, 2620:1ec:bda:700::2 AS8075
windowsmobile.dkns1-04.azure-dns.com 13.107.236.4 AS8075, 2603:1061:0:700::4 AS8075
ns2-04.azure-dns.net 150.171.21.4 AS8075, 2620:1ec:8ec:700::4 AS8075
ns3-04.azure-dns.org 204.14.183.4 AS8075, 2a01:111:4000:700::4 AS8075
ns4-04.azure-dns.info 208.84.5.4 AS8075, 2620:1ec:bda:700::4 AS8075
windowsphone.dkns1-07.azure-dns.com 13.107.236.7 AS8075, 2603:1061:0:700::7 AS8075
ns2-07.azure-dns.net 150.171.21.7 AS8075, 2620:1ec:8ec:700::7 AS8075
ns3-07.azure-dns.org 204.14.183.7 AS8075, 2a01:111:4000:700::7 AS8075
ns4-07.azure-dns.info 208.84.5.7 AS8075, 2620:1ec:bda:700::7 AS8075
windowsphone7.dkns1-03.azure-dns.com 13.107.236.3 AS8075, 2603:1061:0:700::3 AS8075
ns2-03.azure-dns.net 150.171.21.3 AS8075, 2620:1ec:8ec:700::3 AS8075
ns3-03.azure-dns.org 204.14.183.3 AS8075, 2a01:111:4000:700::3 AS8075
ns4-03.azure-dns.info 208.84.5.3 AS8075, 2620:1ec:bda:700::3 AS8075
windowsphones.dkns1-02.azure-dns.com 13.107.236.2 AS8075, 2603:1061:0:700::2 AS8075
ns2-02.azure-dns.net 150.171.21.2 AS8075, 2620:1ec:8ec:700::2 AS8075
ns3-02.azure-dns.org 204.14.183.2 AS8075, 2a01:111:4000:700::2 AS8075
ns4-02.azure-dns.info 208.84.5.2 AS8075, 2620:1ec:bda:700::2 AS8075
windowsserver.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
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