🛡️ 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

1,183,339 working delegations with resolvable nameservers (lame excluded)
Every nameserver is on…DomainsShareWhy it matters
A single nameserver host1460.01%Any outage or mistake on that host takes the domain offline; RFC 1034 asks for at least two.
A single nameserver address1,3090.11%Several NS names, but they all resolve to one IP, so they are really one server.
One IPv4 /24 and no IPv610,6840.90%All nameservers share one network: a routing problem there takes them all down.
One autonomous system757,75064.0%Common and usually fine with a large provider, but one network outage still takes all nameservers down.
No IPv6 nameserver85,1697.2%IPv6-only resolvers cannot reach the zone.

Click a row to list its domains (computed 2026-10-06 00:32).

📋 One autonomous system

757,750 domains
DomainNameservers and addresses
agrowa.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
agrowatch.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
agroweb.dkpns41.cloudns.net 185.136.96.79 AS203391, 2a06:fb00:1::1:79 AS203391
pns42.cloudns.net 185.136.97.79 AS203391, 2a06:fb00:1::2:79 AS203391
pns43.cloudns.net 185.136.98.79 AS203391, 2a06:fb00:1::3:79 AS203391
pns44.cloudns.net 185.136.99.79 AS203391, 2a06:fb00:1::4:79 AS203391
agroweekend.dkpns41.cloudns.net 185.136.96.79 AS203391, 2a06:fb00:1::1:79 AS203391
pns42.cloudns.net 185.136.97.79 AS203391, 2a06:fb00:1::2:79 AS203391
pns43.cloudns.net 185.136.98.79 AS203391, 2a06:fb00:1::3:79 AS203391
pns44.cloudns.net 185.136.99.79 AS203391, 2a06:fb00:1::4:79 AS203391
agrowgrass.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
agrowline.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
agrowmaize.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
agrowseed.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
agrowseeds.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
agroxperten.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
agroøkologi.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
agrtest.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
agruppen.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
ags-cloud.dkdarwin.ns.cloudflare.com 108.162.193.151 AS13335, 172.64.33.151 AS13335, 173.245.59.151 AS13335, 2606:4700:58::adf5:3b97 AS13335, 2803:f800:50::6ca2:c197 AS13335, 2a06:98c1:50::ac40:2197 AS13335
lina.ns.cloudflare.com 108.162.192.187 AS13335, 172.64.32.187 AS13335, 173.245.58.187 AS13335, 2606:4700:50::adf5:3abb AS13335, 2803:f800:50::6ca2:c0bb AS13335, 2a06:98c1:50::ac40:20bb AS13335
ags-maskiner.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
agsdanmark.dkcourtney.ns.cloudflare.com 108.162.194.130 AS13335, 162.159.38.130 AS13335, 172.64.34.130 AS13335, 2606:4700:50::a29f:2682 AS13335, 2803:f800:50::6ca2:c282 AS13335, 2a06:98c1:50::ac40:2282 AS13335
mcgrory.ns.cloudflare.com 108.162.195.170 AS13335, 162.159.44.170 AS13335, 172.64.35.170 AS13335, 2606:4700:58::a29f:2caa AS13335, 2803:f800:50::6ca2:c3aa AS13335, 2a06:98c1:50::ac40:23aa AS13335
agsforeningen.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
agsikring.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
agskovservice.dkalfred.ns.cloudflare.com 108.162.195.131 AS13335, 162.159.44.131 AS13335, 172.64.35.131 AS13335, 2606:4700:58::a29f:2c83 AS13335, 2803:f800:50::6ca2:c383 AS13335, 2a06:98c1:50::ac40:2383 AS13335
isla.ns.cloudflare.com 108.162.192.119 AS13335, 172.64.32.119 AS13335, 173.245.58.119 AS13335, 2606:4700:50::adf5:3a77 AS13335, 2803:f800:50::6ca2:c077 AS13335, 2a06:98c1:50::ac40:2077 AS13335
agsocials.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
agst.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
agstnerbyg.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
agsundhed.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
agsundhedsfremme.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
agt-bilpleje.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
agt.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
agtb.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
agterapi.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
agtex.dklex.ns.cloudflare.com 108.162.193.196 AS13335, 172.64.33.196 AS13335, 173.245.59.196 AS13335, 2606:4700:58::adf5:3bc4 AS13335, 2803:f800:50::6ca2:c1c4 AS13335, 2a06:98c1:50::ac40:21c4 AS13335
mona.ns.cloudflare.com 108.162.192.206 AS13335, 172.64.32.206 AS13335, 173.245.58.206 AS13335, 2606:4700:50::adf5:3ace AS13335, 2803:f800:50::6ca2:c0ce AS13335, 2a06:98c1:50::ac40:20ce AS13335
agtig.dkns1.dreamhost.com 162.159.26.14 AS13335
ns2.dreamhost.com 162.159.26.81 AS13335
ns3.dreamhost.com 162.159.27.84 AS13335
agtnordicgroup.dkns1.eksakte.dk 185.25.141.12 AS48854, 2a02:2339:4006:108::123 AS48854
ns2.eksakte.dk 2a02:2339:1:10f::123:123 AS48854, 91.197.248.75 AS48854
agtoemrer.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
agtomrer.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
agtpaper.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
agtrup-plast.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
agtrupvig.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
agts.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
agu-online.dkns1.esis.dk 185.19.134.2 AS199374
ns2.esis.dk 185.19.134.3 AS199374
agua.dkns1.web24tech.com 85.215.129.49 AS8560
ns2.web24tech.com 85.215.133.5 AS8560
aguacell.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
aguard.dkns1.instradns.com 75.2.6.34 AS16509
ns2.instradns.com 75.2.85.37 AS16509
ns3.instradns.com 99.83.188.20 AS16509
aguardente.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
aguasol.dkcody.ns.cloudflare.com 108.162.193.107 AS13335, 172.64.33.107 AS13335, 173.245.59.107 AS13335, 2606:4700:58::adf5:3b6b AS13335, 2803:f800:50::6ca2:c16b AS13335, 2a06:98c1:50::ac40:216b AS13335
crystal.ns.cloudflare.com 108.162.194.202 AS13335, 162.159.38.202 AS13335, 172.64.34.202 AS13335, 2606:4700:50::a29f:26ca AS13335, 2803:f800:50::6ca2:c2ca AS13335, 2a06:98c1:50::ac40:22ca AS13335
aguettant.dkdns104.ovh.net 2001:41d0:d00:fe00::2 AS16276, 5.196.39.113 AS16276
ns104.ovh.net 2001:41d0:b00:f800::2 AS16276, 5.135.60.17 AS16276
aguettantnordic.dkdns104.ovh.net 2001:41d0:d00:fe00::2 AS16276, 5.196.39.113 AS16276
ns104.ovh.net 2001:41d0:b00:f800::2 AS16276, 5.135.60.17 AS16276
aguiar.dkchuck.ns.cloudflare.com 108.162.193.86 AS13335, 172.64.33.86 AS13335, 173.245.59.86 AS13335, 2606:4700:58::adf5:3b56 AS13335, 2803:f800:50::6ca2:c156 AS13335, 2a06:98c1:50::ac40:2156 AS13335
nelly.ns.cloudflare.com 108.162.192.209 AS13335, 172.64.32.209 AS13335, 173.245.58.209 AS13335, 2606:4700:50::adf5:3ad1 AS13335, 2803:f800:50::6ca2:c0d1 AS13335, 2a06:98c1:50::ac40:20d1 AS13335
aguilar-hoey.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
aguldager.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
agulvafslibning.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
aguonline.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
dhd.dk [/] search Domains, Hosts & DNS — .dk zone