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BuddyNS delegation lab

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Color Indication Color Indication Color Indication
  Zone.   Nameserver serving outdated data.   Nameserver from the BuddyNS backbone.
  Nameserver delegated by zone.   Server was queried and timed out.   Inconsistency between zone and registry.

Geographical distribution of the Authority servers

Location Server

Geographical locations are established via MaxMind's GeoLite technology. Some locations may be inexact.

Delegation tests for qmail.jp

Test Result Notes
Is Zone OK The indicated domain qmail.jp is a zone: authority and nameserver data is announced for it. These are the authority parameters for zone qmail.jp:
Master
a.ns.qmail.jp.
Administrator
hostmaster@m.qmail.jp
Version serial
1711662377
Slave refresh
16384
Slave retry
2048
Slave expiry
1048576
Negative cache
900
Zone/Registry consistent OK The list of nameservers declared by the last delegating server and the authoritative server match. Configuration looks healthy.
Authoritative servers consistent ERROR Authoritative nameservers for qmail.jp are serving inconsistent data. Clients may be confused by getting different answers depending on what destination nameserver they reached. The outdated zone data some nameservers are publishing may reference records pointing clients to IP addresses no longer in control of qmail.jp's organization, thus incurring data and identity theft. Serial numbers are:
  • a.ns.qmail.jp: #1711629591
  • b.ns.qmail.jp: #1711662377
  • d.ns.qmail.jp: #1711662377
Number of servers OK qmail.jp delegates its DNS to 3 servers. This is a sufficient number to provide DNS continuity. RFC 2182 recommends 3 to 5 servers "when higher reliability is required": BuddyNS recommends 4 or 5.
Unresponsive nameservers OK All queried nameservers responded; no dead/misconfigured/unavailable server was found in the chosen resolution path.
Recursion OK None of the DNS servers listed as authoritative for qmail.jp serves recursive queries to the public.
Truncation OK None of the DNS servers listed as authoritative for qmail.jp gives a truncated response for NS requests. Clients can successfully perform NS queries over the low-latency UDP protocol, without falling back to much slower TCP.
IPv6 WARNING None of the servers serving qmail.jp's DNS is reachable via IPv6. IPv6-enabled clients qmail.jp will need to revert to compatibility IPv4 protocol for every look up of services of qmail.jp. A growing number a IPv6-only clients will be unable to perform such look ups.

IPv6 score: 0%

DNSCurve No DNScurve is not supported for this zone. To leverage DNSCurve from BuddyNS, delegate qmail.jp using secure server names from BuddyNS.

Delegation trace for qmail.jp

Notes

The delegation trace below is one of the possible traversals of the delegation tree. Note that:

  • For zones with correct delegation, the same data is obtained regardless of which resolution path is traversed.
  • BuddyNS excludes its own servers from traversals when foreign servers are available.
  • Refresh this page to test with a different traversal path.

Here's the steps BuddyNS took to collect the DNS delegation chain for qmail.jp: