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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   Nameserver serving outdated data.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 com

Test Result Notes
Is Zone OK The indicated domain com is a zone: authority and nameserver data is announced for it. These are the authority parameters for zone com:
Master
a.gtld-servers.net.
Administrator
nstld@verisign-grs.com
Version serial
1731659943
Slave refresh
1800
Slave retry
900
Slave expiry
604800
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 OK Every nameserver authoritative for com correctly serves the same zone version, so client queries will get the same response regardless of the server they reach. Here's the summary:
  • l.gtld-servers.net → #1731659943
  • f.gtld-servers.net → #1731659943
  • j.gtld-servers.net → #1731659943
  • c.gtld-servers.net → #1731659943
  • d.gtld-servers.net → #1731659943
  • h.gtld-servers.net → #1731659943
  • a.gtld-servers.net → #1731659943
  • k.gtld-servers.net → #1731659943
  • b.gtld-servers.net → #1731659943
  • g.gtld-servers.net → #1731659943
  • m.gtld-servers.net → #1731659943
  • i.gtld-servers.net → #1731659943
  • e.gtld-servers.net → #1731659943
Number of servers WARNING com delegates its DNS to 13 servers. There are very few advantages in running more than 5 servers, and some disadvantages:
  • Bigger response packets. Some DNS implementations of these servers may cause TrunCation (TC) of DNS responses, based on how they build the Additional section. This causes major slowdowns, and in some cases entire resolution errors.
  • Harder maintenance. Each system is as weak as its weakest node.
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 com serves recursive queries to the public.
Truncation OK None of the DNS servers listed as authoritative for com 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 OK The authority declares one or more servers as reachable via IPv6. IPv6-enabled clients can resolve domains of com natively, without falling back to the compatibility IPv4 protocol.

IPv6 score: 100%

Here is the list of IPv6-enabled servers declared by com:
  • l.gtld-servers.net → 2001:500:d937::30
  • f.gtld-servers.net → 2001:503:d414::30
  • j.gtld-servers.net → 2001:502:7094::30
  • c.gtld-servers.net → 2001:503:83eb::30
  • d.gtld-servers.net → 2001:500:856e::30
  • h.gtld-servers.net → 2001:502:8cc::30
  • a.gtld-servers.net → 2001:503:a83e::2:30
  • k.gtld-servers.net → 2001:503:d2d::30
  • b.gtld-servers.net → 2001:503:231d::2:30
  • g.gtld-servers.net → 2001:503:eea3::30
  • m.gtld-servers.net → 2001:501:b1f9::30
  • i.gtld-servers.net → 2001:503:39c1::30
  • e.gtld-servers.net → 2001:502:1ca1::30
DNSCurve No DNScurve is not supported for this zone. To leverage DNSCurve from BuddyNS, delegate com using secure server names from BuddyNS.

Delegation trace for com

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 com: