🛡️ 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

1,185,859 working delegations with resolvable nameservers (lame excluded)
Every nameserver is on…DomainsShareWhy it matters
A single nameserver host1470.01%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 IPv610,7960.91%All nameservers share one network: a routing problem there takes them all down.
One autonomous system758,38264.0%Common and usually fine with a large provider, but one network outage still takes all nameservers down.
No IPv6 nameserver85,8087.2%IPv6-only resolvers cannot reach the zone.

Click a row to list its domains (computed 2026-10-01 08:10).

📋 One autonomous system

758,382 domains
DomainNameservers and addresses
4653.dkns1.wsd.dk 193.150.84.89 AS31027
ns2.wsd.dk 193.150.84.90 AS31027
ns3.wsd.dk 193.150.84.91 AS31027
4653karise.dkns7.bricksite.net 35.246.226.10 AS396982
ns8.bricksite.net 35.242.190.82 AS396982
4654.dkns1.wsd.dk 193.150.84.89 AS31027
ns2.wsd.dk 193.150.84.90 AS31027
ns3.wsd.dk 193.150.84.91 AS31027
4660.dkns1.wsd.dk 193.150.84.89 AS31027
ns2.wsd.dk 193.150.84.90 AS31027
ns3.wsd.dk 193.150.84.91 AS31027
46664.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
4671.dkns1.wsd.dk 193.150.84.89 AS31027
ns2.wsd.dk 193.150.84.90 AS31027
ns3.wsd.dk 193.150.84.91 AS31027
4672.dkns1.wsd.dk 193.150.84.89 AS31027
ns2.wsd.dk 193.150.84.90 AS31027
ns3.wsd.dk 193.150.84.91 AS31027
4673.dkns1.wsd.dk 193.150.84.89 AS31027
ns2.wsd.dk 193.150.84.90 AS31027
ns3.wsd.dk 193.150.84.91 AS31027
4681.dkns1.wsd.dk 193.150.84.89 AS31027
ns2.wsd.dk 193.150.84.90 AS31027
ns3.wsd.dk 193.150.84.91 AS31027
4682.dkns1.wsd.dk 193.150.84.89 AS31027
ns2.wsd.dk 193.150.84.90 AS31027
ns3.wsd.dk 193.150.84.91 AS31027
4683.dkns1.wsd.dk 193.150.84.89 AS31027
ns2.wsd.dk 193.150.84.90 AS31027
ns3.wsd.dk 193.150.84.91 AS31027
4684.dkns1.wsd.dk 193.150.84.89 AS31027
ns2.wsd.dk 193.150.84.90 AS31027
ns3.wsd.dk 193.150.84.91 AS31027
4690-haslev.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
4690.dkns1.wsd.dk 193.150.84.89 AS31027
ns2.wsd.dk 193.150.84.90 AS31027
ns3.wsd.dk 193.150.84.91 AS31027
46913020.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
46films.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
46gn.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
46gradernord.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
47.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
4700fugleparken.dkns4.dns-123.net 35.198.132.83 AS396982
ns5.dns-123.net 35.187.184.173 AS396982
ns6.dns-123.net 35.228.54.1 AS396982
4700holding.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
4700swim.dkamber.ns.cloudflare.com 108.162.192.64 AS13335, 172.64.32.64 AS13335, 173.245.58.64 AS13335, 2606:4700:50::adf5:3a40 AS13335, 2803:f800:50::6ca2:c040 AS13335, 2a06:98c1:50::ac40:2040 AS13335
hayes.ns.cloudflare.com 108.162.195.245 AS13335, 162.159.44.245 AS13335, 172.64.35.245 AS13335, 2606:4700:58::a29f:2cf5 AS13335, 2803:f800:50::6ca2:c3f5 AS13335, 2a06:98c1:50::ac40:23f5 AS13335
4700udlejning.dkcheryl.ns.cloudflare.com 108.162.192.83 AS13335, 172.64.32.83 AS13335, 173.245.58.83 AS13335, 2606:4700:50::adf5:3a53 AS13335, 2803:f800:50::6ca2:c053 AS13335, 2a06:98c1:50::ac40:2053 AS13335
seth.ns.cloudflare.com 108.162.193.142 AS13335, 172.64.33.142 AS13335, 173.245.59.142 AS13335, 2606:4700:58::adf5:3b8e AS13335, 2803:f800:50::6ca2:c18e AS13335, 2a06:98c1:50::ac40:218e AS13335
47181818.dkgate.profdoc.dk 80.62.243.243 AS3292
ns.profdoc.dk 80.62.243.242 AS3292
4736.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
4750.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
4760-net.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
4760net.dkleif.ns.cloudflare.com 108.162.195.222 AS13335, 162.159.44.222 AS13335, 172.64.35.222 AS13335, 2606:4700:58::a29f:2cde AS13335, 2803:f800:50::6ca2:c3de AS13335, 2a06:98c1:50::ac40:23de AS13335
michelle.ns.cloudflare.com 108.162.192.201 AS13335, 172.64.32.201 AS13335, 173.245.58.201 AS13335, 2606:4700:50::adf5:3ac9 AS13335, 2803:f800:50::6ca2:c0c9 AS13335, 2a06:98c1:50::ac40:20c9 AS13335
479235.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
47937033.dkgate.profdoc.dk 80.62.243.243 AS3292
ns.profdoc.dk 80.62.243.242 AS3292
47brand.dksl1.sedo.com 91.195.240.173 AS47846
sl2.sedo.com 91.195.241.173 AS47846
4815162342.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
48240027.dkgate.profdoc.dk 80.62.243.243 AS3292
ns.profdoc.dk 80.62.243.242 AS3292
48241200.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
48242240.dkns01.danskinternet.dk 185.25.141.12 AS48854, 2a02:2339:4006:108::123 AS48854
ns02.danskinternet.dk 2a02:2339:1:10f::123:123 AS48854, 91.197.248.75 AS48854
48260056.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
48260177.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
48261701.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
48267999.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
48300204.dkgate.profdoc.dk 80.62.243.243 AS3292
ns.profdoc.dk 80.62.243.242 AS3292
485.dkns1-06.azure-dns.com 13.107.236.6 AS8075, 2603:1061:0:700::6 AS8075
ns2-06.azure-dns.net 150.171.21.6 AS8075, 2620:1ec:8ec:700::6 AS8075
ns3-06.azure-dns.org 204.14.183.6 AS8075, 2a01:111:4000:700::6 AS8075
ns4-06.azure-dns.info 208.84.5.6 AS8075, 2620:1ec:bda:700::6 AS8075
4850.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
4873.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
48765555.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
48c.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
48halvtreds.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
48hofhygge.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
48k-test.dkpoppy.ns.cloudflare.com 108.162.194.33 AS13335, 162.159.38.33 AS13335, 172.64.34.33 AS13335, 2606:4700:50::a29f:2621 AS13335, 2803:f800:50::6ca2:c221 AS13335, 2a06:98c1:50::ac40:2221 AS13335
ram.ns.cloudflare.com 108.162.193.225 AS13335, 172.64.33.225 AS13335, 173.245.59.225 AS13335, 2606:4700:58::adf5:3be1 AS13335, 2803:f800:50::6ca2:c1e1 AS13335, 2a06:98c1:50::ac40:21e1 AS13335
48k.dkpoppy.ns.cloudflare.com 108.162.194.33 AS13335, 162.159.38.33 AS13335, 172.64.34.33 AS13335, 2606:4700:50::a29f:2621 AS13335, 2803:f800:50::6ca2:c221 AS13335, 2a06:98c1:50::ac40:2221 AS13335
ram.ns.cloudflare.com 108.162.193.225 AS13335, 172.64.33.225 AS13335, 173.245.59.225 AS13335, 2606:4700:58::adf5:3be1 AS13335, 2803:f800:50::6ca2:c1e1 AS13335, 2a06:98c1:50::ac40:21e1 AS13335
48timer.dkns.domainteam.dk 87.238.248.151 AS198614
ns2.domainteam.dk 185.200.74.103 AS198614
dhd.dk [/] search Domains, Hosts & DNS — .dk zone