🛡️ 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

1,183,542 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 address1,3040.11%Several NS names, but they all resolve to one IP, so they are really one server.
One IPv4 /24 and no IPv610,6770.90%All nameservers share one network: a routing problem there takes them all down.
One autonomous system758,00864.0%Common and usually fine with a large provider, but one network outage still takes all nameservers down.
No IPv6 nameserver85,4057.2%IPv6-only resolvers cannot reach the zone.

Click a row to list its domains (computed 2026-10-05 05:55).

📋 One autonomous system

758,008 domains
DomainNameservers and addresses
acenetworx.dksid.ns.cloudflare.com 108.162.193.143 AS13335, 172.64.33.143 AS13335, 173.245.59.143 AS13335, 2606:4700:58::adf5:3b8f AS13335, 2803:f800:50::6ca2:c18f AS13335, 2a06:98c1:50::ac40:218f AS13335
sierra.ns.cloudflare.com 108.162.194.245 AS13335, 162.159.38.245 AS13335, 172.64.34.245 AS13335, 2606:4700:50::a29f:26f5 AS13335, 2803:f800:50::6ca2:c2f5 AS13335, 2a06:98c1:50::ac40:22f5 AS13335
acent.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
acenta.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
acentarecruit.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
acenti.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
acentia.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
acentio.dkhasslo.ns.cloudflare.com 108.162.195.134 AS13335, 162.159.44.134 AS13335, 172.64.35.134 AS13335, 2606:4700:58::a29f:2c86 AS13335, 2803:f800:50::6ca2:c386 AS13335, 2a06:98c1:50::ac40:2386 AS13335
melany.ns.cloudflare.com 108.162.194.138 AS13335, 162.159.38.138 AS13335, 172.64.34.138 AS13335, 2606:4700:50::a29f:268a AS13335, 2803:f800:50::6ca2:c28a AS13335, 2a06:98c1:50::ac40:228a AS13335
acentiobiz.dkarnold.ns.cloudflare.com 108.162.193.69 AS13335, 172.64.33.69 AS13335, 173.245.59.69 AS13335, 2606:4700:58::adf5:3b45 AS13335, 2803:f800:50::6ca2:c145 AS13335, 2a06:98c1:50::ac40:2145 AS13335
vita.ns.cloudflare.com 108.162.192.238 AS13335, 172.64.32.238 AS13335, 173.245.58.238 AS13335, 2606:4700:50::adf5:3aee AS13335, 2803:f800:50::6ca2:c0ee AS13335, 2a06:98c1:50::ac40:20ee AS13335
acentreprenorforretning.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
aceo-group.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
aceofbeton.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
acepvp.dknia.ns.cloudflare.com 108.162.192.210 AS13335, 172.64.32.210 AS13335, 173.245.58.210 AS13335, 2606:4700:50::adf5:3ad2 AS13335, 2803:f800:50::6ca2:c0d2 AS13335, 2a06:98c1:50::ac40:20d2 AS13335
theo.ns.cloudflare.com 108.162.193.144 AS13335, 172.64.33.144 AS13335, 173.245.59.144 AS13335, 2606:4700:58::adf5:3b90 AS13335, 2803:f800:50::6ca2:c190 AS13335, 2a06:98c1:50::ac40:2190 AS13335
acequeen.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
acer.dkns-1488.awsdns-58.org 205.251.197.208 AS16509, 2600:9000:5305:d000::1 AS16509
ns-1730.awsdns-24.co.uk 205.251.198.194 AS16509, 2600:9000:5306:c200::1 AS16509
ns-409.awsdns-51.com 205.251.193.153 AS16509, 2600:9000:5301:9900::1 AS16509
ns-896.awsdns-48.net 205.251.195.128 AS16509, 2600:9000:5303:8000::1 AS16509
acer4all.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
acerace.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
aceram.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
acercon.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
acerental.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
acero.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
acert.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
acesionpharma.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
acesmc.dknia.ns.cloudflare.com 108.162.192.210 AS13335, 172.64.32.210 AS13335, 173.245.58.210 AS13335, 2606:4700:50::adf5:3ad2 AS13335, 2803:f800:50::6ca2:c0d2 AS13335, 2a06:98c1:50::ac40:20d2 AS13335
theo.ns.cloudflare.com 108.162.193.144 AS13335, 172.64.33.144 AS13335, 173.245.59.144 AS13335, 2606:4700:58::adf5:3b90 AS13335, 2803:f800:50::6ca2:c190 AS13335, 2a06:98c1:50::ac40:2190 AS13335
acesohealth.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
acesolutions.dkns1-37.azure-dns.com 150.171.10.37 AS8075, 2603:1061:0:10::25 AS8075
ns2-37.azure-dns.net 150.171.16.37 AS8075, 2620:1ec:8ec:10::25 AS8075
ns3-37.azure-dns.org 13.107.222.37 AS8075, 2a01:111:4000:10::25 AS8075
ns4-37.azure-dns.info 13.107.206.37 AS8075, 2620:1ec:bda:10::25 AS8075
acesonordic.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
acesound.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
acespace.dkdexter.ns.cloudflare.com 108.162.195.190 AS13335, 162.159.44.190 AS13335, 172.64.35.190 AS13335, 2606:4700:58::a29f:2cbe AS13335, 2803:f800:50::6ca2:c3be AS13335, 2a06:98c1:50::ac40:23be AS13335
simone.ns.cloudflare.com 108.162.194.26 AS13335, 162.159.38.26 AS13335, 172.64.34.26 AS13335, 2606:4700:50::a29f:261a AS13335, 2803:f800:50::6ca2:c21a AS13335, 2a06:98c1:50::ac40:221a AS13335
acessivel.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
acestate.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
acestudio.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
acet.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
acetech.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
acetone.dknoel.ns.cloudflare.com 108.162.193.216 AS13335, 172.64.33.216 AS13335, 173.245.59.216 AS13335, 2606:4700:58::adf5:3bd8 AS13335, 2803:f800:50::6ca2:c1d8 AS13335, 2a06:98c1:50::ac40:21d8 AS13335
ulla.ns.cloudflare.com 108.162.192.233 AS13335, 172.64.32.233 AS13335, 173.245.58.233 AS13335, 2606:4700:50::adf5:3ae9 AS13335, 2803:f800:50::6ca2:c0e9 AS13335, 2a06:98c1:50::ac40:20e9 AS13335
acetus.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
acetylen.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
acewinner.dkdns1.idp365.net 162.159.27.131 AS13335, 2400:cb00:2049:1::a29f:1b83 AS13335
dns2.idp365.net 162.159.48.3 AS13335, 2400:cb00:2049:1::a29f:3003 AS13335
dns3.idp365.net 162.159.49.254 AS13335, 2400:cb00:2049:1::a29f:31fe AS13335
aceworks.dkapollo.ns.cloudflare.com 108.162.193.66 AS13335, 172.64.33.66 AS13335, 173.245.59.66 AS13335, 2606:4700:58::adf5:3b42 AS13335, 2803:f800:50::6ca2:c142 AS13335, 2a06:98c1:50::ac40:2142 AS13335
roxy.ns.cloudflare.com 108.162.192.142 AS13335, 172.64.32.142 AS13335, 173.245.58.142 AS13335, 2606:4700:50::adf5:3a8e AS13335, 2803:f800:50::6ca2:c08e AS13335, 2a06:98c1:50::ac40:208e AS13335
acfinance.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
acfinans.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
acgbyg.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
acgnystrom.dkelisabeth.ns.cloudflare.com 108.162.194.224 AS13335, 162.159.38.224 AS13335, 172.64.34.224 AS13335, 2606:4700:50::a29f:26e0 AS13335, 2803:f800:50::6ca2:c2e0 AS13335, 2a06:98c1:50::ac40:22e0 AS13335
norm.ns.cloudflare.com 108.162.193.134 AS13335, 172.64.33.134 AS13335, 173.245.59.134 AS13335, 2606:4700:58::adf5:3b86 AS13335, 2803:f800:50::6ca2:c186 AS13335, 2a06:98c1:50::ac40:2186 AS13335
acgroup.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
acgruppen.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
acgrus.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
achahbi.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
achaker.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
achbiler.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
achconsult.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
achdk.dkns-1311.awsdns-35.org 205.251.197.31 AS16509, 2600:9000:5305:1f00::1 AS16509
ns-136.awsdns-17.com 205.251.192.136 AS16509, 2600:9000:5300:8800::1 AS16509
ns-1815.awsdns-34.co.uk 205.251.199.23 AS16509, 2600:9000:5307:1700::1 AS16509
ns-921.awsdns-51.net 205.251.195.153 AS16509, 2600:9000:5303:9900::1 AS16509
dhd.dk [/] search Domains, Hosts & DNS — .dk zone