Different results on 8.8.8.8 and 8.8.4.4

[Wichu]

Hi,

The correct IP would be: 176.9.97.162 as the 8.8.8.8 always has:

C:\Users\WichuNew>nslookup - 8.8.8.8
Default Server: google-public-dns-a.google.com
Address: 8.8.8.8

> set debug
> wichu.ch
Server: google-public-dns-a.google.com
Address: 8.8.8.8

------------
Got answer:
HEADER:
opcode = QUERY, id = 2, rcode = NXDOMAIN
header flags: response, want recursion, recursion avail.
questions = 1, answers = 0, authority records = 1,
additional = 0

QUESTIONS:
wichu.ch.vt.ch, type = A, class = IN
AUTHORITY RECORDS:
-> ch
ttl = 1641 (27 mins 21 secs)
primary name server = a.nic.ch
responsible mail addr = helpdesk.nic.ch
serial = 2012033023
refresh = 3600 (1 hour)
retry = 900 (15 mins)
expire = 1209600 (14 days)
default TTL = 3600 (1 hour)

------------
------------
Got answer:
HEADER:
opcode = QUERY, id = 3, rcode = NXDOMAIN
header flags: response, want recursion, recursion avail.
questions = 1, answers = 0, authority records = 1,
additional = 0

QUESTIONS:
wichu.ch.vt.ch, type = AAAA, class = IN
AUTHORITY RECORDS:
-> ch
ttl = 1641 (27 mins 21 secs)
primary name server = a.nic.ch
responsible mail addr = helpdesk.nic.ch
serial = 2012033023
refresh = 3600 (1 hour)
retry = 900 (15 mins)
expire = 1209600 (14 days)
default TTL = 3600 (1 hour)

------------
------------
Got answer:
HEADER:
opcode = QUERY, id = 4, rcode = NOERROR
header flags: response, want recursion, recursion avail.
questions = 1, answers = 1, authority records = 0,
additional = 0

QUESTIONS:
wichu.ch, type = A, class = IN
ANSWERS:
-> wichu.ch
internet address = 176.9.97.162
ttl = 100 (1 min 40 secs)

------------
Non-authoritative answer:
------------
Got answer:
HEADER:
opcode = QUERY, id = 5, rcode = NOERROR
header flags: response, want recursion, recursion avail.
questions = 1, answers = 0, authority records = 1,
additional = 0

QUESTIONS:
wichu.ch, type = AAAA, class = IN
AUTHORITY RECORDS:
-> wichu.ch
ttl = 100 (1 min 40 secs)
primary name server = ns1.wichu.net
responsible mail addr = master.wichu.ch
serial = 2012033011
refresh = 28800 (8 hours)
retry = 7200 (2 hours)
expire = 100 (1 min 40 secs)
default TTL = 100 (1 min 40 secs)

------------
Name: wichu.ch
Address: 176.9.97.162


And the wrong one (old one):

C:\Users\WichuNew>nslookup - 8.8.4.4
Default Server: google-public-dns-b.google.com
Address: 8.8.4.4

> set debug
> wichu.ch
Server: google-public-dns-b.google.com
Address: 8.8.4.4

------------
Got answer:
HEADER:
opcode = QUERY, id = 2, rcode = NXDOMAIN
header flags: response, want recursion, recursion avail.
questions = 1, answers = 0, authority records = 1,
additional = 0

QUESTIONS:
wichu.ch.vt.ch, type = A, class = IN
AUTHORITY RECORDS:
-> ch
ttl = 1602 (26 mins 42 secs)
primary name server = a.nic.ch
responsible mail addr = helpdesk.nic.ch
serial = 2012033023
refresh = 3600 (1 hour)
retry = 900 (15 mins)
expire = 1209600 (14 days)
default TTL = 3600 (1 hour)

------------
------------
Got answer:
HEADER:
opcode = QUERY, id = 3, rcode = NXDOMAIN
header flags: response, want recursion, recursion avail.
questions = 1, answers = 0, authority records = 1,
additional = 0

QUESTIONS:
wichu.ch.vt.ch, type = AAAA, class = IN
AUTHORITY RECORDS:
-> ch
ttl = 1602 (26 mins 42 secs)
primary name server = a.nic.ch
responsible mail addr = helpdesk.nic.ch
serial = 2012033023
refresh = 3600 (1 hour)
retry = 900 (15 mins)
expire = 1209600 (14 days)
default TTL = 3600 (1 hour)

------------
------------
Got answer:
HEADER:
opcode = QUERY, id = 4, rcode = NOERROR
header flags: response, want recursion, recursion avail.
questions = 1, answers = 1, authority records = 0,
additional = 0

QUESTIONS:
wichu.ch, type = A, class = IN
ANSWERS:
-> wichu.ch
internet address = 176.9.77.189
ttl = 73004 (20 hours 16 mins 44 secs)

------------
Non-authoritative answer:
------------
Got answer:
HEADER:
opcode = QUERY, id = 5, rcode = NOERROR
header flags: response, want recursion, recursion avail.
questions = 1, answers = 0, authority records = 1,
additional = 0

QUESTIONS:
wichu.ch, type = AAAA, class = IN
AUTHORITY RECORDS:
-> wichu.ch
ttl = 34 (34 secs)
primary name server = ns1.wichu.net
responsible mail addr = master.wichu.ch
serial = 2012033011
refresh = 28800 (8 hours)
retry = 7200 (2 hours)
expire = 100 (1 min 40 secs)
default TTL = 100 (1 min 40 secs)

------------
Name: wichu.ch
Address: 176.9.77.189


On a site note: 8.8.4.4 sometimes returns the correct IP, but most of
the time (9 out of 10) it gives me the old one ...

Hope someone can explain this to me.

Kind regards,
Stefan Wichmann

[Paul S. R. Chisholm]

Sorry for the problem you saw, and thanks for the report. wichu.ch is now resolving correctly (to 176.9.97.162) from all Google Public DNS locations.

An explanation: Whether you use 8.8.8.8 or 8.8.4.4, anycast sends you to a group of machines near you. It's possible that different machines in that group can get out of sync with each other (until time-to-live expires). In your case, if (hypothetically) there was a group of ten machines near you, one with a different answer than the other nine, and you queried 8.8.8.8 ten times, you'd expect to get one answer nine times and the another answer one time. Query 8.8.4.4 ten times, and you'd see the same thing.

Hope this helps (and helps explain).  --PSRC