Forum

Subject: bug on ptr

16/03/2009 10:28 Rimifon:

nslookup
set q=ptr
[define domains in smallsrv]

then other dns servers will refuse smallsrv?

16/03/2009 10:35 Rimifon:

C:\>nslookup
Default Server: dns1.cs.hn.cn
Address: 202.103.96.68

> set q=ptr
> smallsrv.com
Server: dns1.cs.hn.cn
Address: 202.103.96.68

*** dns1.cs.hn.cn can't find smallsrv.com: Non-existent domain
> set q=all
> smallsrv.com
Server: dns1.cs.hn.cn
Address: 202.103.96.68

*** dns1.cs.hn.cn can't find smallsrv.com: Non-existent domain
>

16/03/2009 10:37 Rimifon:

This is OK:
> set q=ptr
> g.cn
Server: dns1.cs.hn.cn
Address: 202.103.96.68

g.cn
primary name server = a.l.google.com
responsible mail addr = dns-admin.google.com
serial = 1374662
refresh = 21600 (6 hours)
retry = 3600 (1 hour)
expire = 1209600 (14 days)
default TTL = 300 (5 mins)
> set q=any
> g.cn
Server: dns1.cs.hn.cn
Address: 202.103.96.68

Not auth-answer:
g.cn internet address = 203.208.39.99
g.cn internet address = 203.208.39.104
>

16/03/2009 11:26 Rimifon:

dns server bug:
C:\>nslookup
Default Server: dns1.cs.hn.cn
Address: 202.103.96.68

> set q=any
> smallsrv.com
Server: dns1.cs.hn.cn
Address: 202.103.96.68

Non-auth??? answer:
smallsrv.com internet address = 84.52.121.78
> set q=ptr
> smallsrv.com
Server: dns1.cs.hn.cn
Address: 202.103.96.68

*** dns1.cs.hn.cn can't find smallsrv.com: Non-existent domain
> set q=all
> smallsrv.com
Server: dns1.cs.hn.cn
Address: 202.103.96.68

*** dns1.cs.hn.cn can't find smallsrv.com: Non-existent domain
>

17/03/2009 13:52 Max:

What is bug? PTR it is record for reverse zone for link between IP address and name. You may add PTR record to your direct zone but, nobody will ask it. PTR record must be in INET.ARPA zone, for correct reply.

17/03/2009 15:05 Rimifon:

But, a wrong PTR request will cause other DNS server to reject SmallSrv.Wrong PTR requested that will cause some local the Internet user to be unable to visit smallsrv.com.

See this:
> set q=all
> smallsrv.com
Server: dns1.cs.hn.cn
Address: 202.103.96.68

Non-auth??? answer:
smallsrv.com internet address = 84.52.121.78
> set q=ptr
> smallsrv.com
Server: dns1.cs.hn.cn
Address: 202.103.96.68

*** dns1.cs.hn.cn can't find smallsrv.com: Non-existent domain
> set q=all
> smallsrv.com
Server: dns1.cs.hn.cn
Address: 202.103.96.68

*** dns1.cs.hn.cn can't find smallsrv.com: Non-existent domain

17/03/2009 15:13 Rimifon:

After wrong ptr request
C:\>ping smallsrv.com
Ping request could not find host smallsrv.com. Please check the name and try again.

19/03/2009 04:53 Rimifon:

why?

20/03/2009 21:28 AnrDaemon:

ipconfig /flushdns
before pinging.
Does your problem persist after resetting local DNS cache?
What is in the server log for both requests (lookup and ping)?

20/03/2009 21:37 AnrDaemon:

One different problem, but DNS related.
hosts file:

12.1.168.192.in-addr.arpa. IN PTR daemon1.darkdragon.

Now,
nslookup -d 192.168.1.12

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

QUESTIONS:
12.1.168.192.in-addr.arpa, type = PTR, class = IN
ANSWERS:
-> 12.1.168.192.in-addr.arpa
name = daemon1.darkdragon
ttl = 86400 (1 day)

*** Error: record size incorrect (20 != 21)

Server: daemon1.darkdragon
Address: 192.168.1.12

W? T? F?