The zone has only one name server.

NS_SINGLE · Severity: Warning

• WarningNS_SINGLE

  The zone has only one name server.

  RFC 1034 section 4.1 asks for at least two name servers for a zone, and RFC 2182 for servers in different networks, so the zone stays reachable when one server or network fails.

  Recommendation: Add a second name server in another network.

Reported by

• Name server check
• Zone file checker

Available through the API

• Name server check API
• Zone file checker API

Related findings

• Info NS_SINGLE_TLD All name servers are under the same top-level domain.
• Warning NS_SAME_NETWORK All name servers are in the same network.
• Info NS_IN_BAILIWICK A name server lies inside the zone it serves and needs glue records.
• Warning NS_NOT_FOUND The name has no NS records.
• Warning NS_UNRESOLVABLE A name server's name has no IPv4 or IPv6 address.

All findings