NS
WAITINGName servers
Enter a domain above to run this check.
NAME SERVERS
CHECK.
List the authoritative name servers of a domain and the IP of each one, and spot an NS that does not resolve, a single server or all on the same network.
Runs only this check. For all 33 checks at once, use the full Domain X-Ray. Public lookups only; nothing is stored on the server.
What the check verifies
Lists the authoritative name servers (NS) of the zone and the IP address of each one.
Why it matters
With a single server, or all of them on the same network, one failure takes the whole domain down. The recommendation is at least two servers on different networks.
What each result means
- OK
- Two or more NS servers answer for the zone, all with an address and on different networks.
- WARNING
- An NS server does not resolve (lame delegation), there is a single server, or all of them are on the same /24 network.
- FAIL
- No NS server was found for the zone.
ERROR and TIMEOUT mean the query did not finish (the source was down or slow), not a problem with the domain: run the check again.
How to fix
Keep at least two name servers on different networks and remove from the registrar the ones that no longer exist. To compare what the registry delegates with what the zone answers:
dig NS example.com +short
dig +trace NS example.comWould rather have someone else do it? Bit Happens can fix this →
More checks in DNS and name servers
Guide: How to troubleshoot DNS →
Full Domain X-Ray: all 33 DNS, email, HTTPS, certificate and reputation checks at once →