Unable to query the nameserver

[Andrey G. Sergeev (AKA Andris)]

Hello Dotan,


Tue, 5 Oct 2010 20:20:02 +0200 Dotan Cohen wrote:

>> Can you successfuly telnet port 53 from an external host?
> 
> Yes, but it's only a connection. I don't see any output. That' me
> typing "helo":
> 
> $ telnet 178.63.65.136 53
> Trying 178.63.65.136...
> Connected to 178.63.65.136.
> Escape character is '^]'.
> helo
> USER test
> ^C^C
> Connection closed by foreign host.

The DNS protocol has no human-readable verbs. The fact that you can
connect to the port 53 from the external location indicates that the
TCP connections aren't blocked. But DNS uses TCP only in a limited
number of cases - most time the UDP protocol is being used for queries.

So you must verify that you _can_ query your server for something like
this:

dig @server-name-or-ip example.de. soa +norec


-- 

Yours sincerely,

Andrey G. Sergeev (AKA Andris)     http://www.andris.name/