[ntp:questions] pool.ntp.org DNS errors & warnings

Guy Macon "http://www.guymacon.com/" at ntp.isc.org
Wed Jun 13 20:37:40 UTC 2007

pool.ntp.org DNS errors & warnings:

DNS Servers for pool.ntp.org:
a.ntpns.org. []
b.ntpns.org. []
c.ntpns.org. []
d.ntpns.org. []
e.ntpns.org. []


The other DNS Servers are closed, but c.ntpns.org. []
is an open DNS server, and responds to queries for domains it is not 
authoritative for. This can cause an excessive load on this DNS server.
Also, this DNS server can be used as part of an attack by forging 
IP address.

The other DNS Servers say that serial # 1181760004 is the latest
version, but e.ntpns.org. [] says that serial # 
1181758808 is the latest version.

The other DNS servers accept TCP connections, but b.ntpns.org 
[] does not.

The SOA (Start of Authority) record states the master (primary) 
name server is ns1.us.bitnames.com, but that server is not listed 
at the parent servers as one of the NS records.

WARNING #3: SOA MINIMUM TTL is 240 seconds. RFC2308 suggests 
a value of 1-3 hours (Is this a bogus error?  Is there a 
reason why this should be shorter than usual because this is 
for an an NTP pool? -Guy)


Guy Macon

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