weird problem when making MX-type DNS queries

[Emilio]

Hello

I've got a problem making DNS queries, from my leased line.
I've been trying to install a Mail Server (Mail Trasfer Agent) but I've
found that DNS queries for MX do not respond in time.
I've used my laptop, with WinXP Pro SP2, for trying DNS queries; using some
tools (nslookup, and PingProbe (a graphical tool)), and always happens the
same scenario:

When I make queries from my leased line connection, A-type DNS queries,
responds sucessfully; but MX-type DNS queries do not.
When I make DNS queries of any type, connected from other leased lines, all
queries are sucessfully treated, and MX-type queries return the
corresponding MX records.

I get response from ping command when pingging to those DNS servers I
usually consult, and because A-type queries get answers, I guess connections
(using port 53) can be established.


I wonder what is happening and if anyone can help me.

Thanks in advance
Emilio

 

[Anteaus]

Are you using an ADSL (broadband) router to perform DNS forwarding? I've
found that the DNS implementations in some do not cater for MX records, hence
if you run a mailserver behind one you will have trouble.

If so, workarounds are to use your ISP's DNS servers directly, or to install
a local server. If you don't have the MS DNS server, alternatives are MaraDNS
(Windows) or dnsmasq (Linux)