Blocking MX query

Bacon Zombie baconzombie at
Tue Sep 4 10:13:21 UTC 2012

Are you saying that you only allow your subscribers to use your DNS Servers
and block access to all other DNS Server?

On 4 September 2012 11:07, Ibrahim <ibrahim1 at> wrote:

> Hi All,
> I've read old archive about blocking SMTP port (TCP port 25). In my current
> situation we are mobile operator and use NAT for our subscribers and we
> have few spammers, a bit difficult to track it because mostly our
> subscribers are prepaid services. If we block TCP port 25, there might be
> "good" subscribers will not be able to send email.
> We are thinking to block MX queries on our DNS server, so only spammer that
> use their own SMTP server will got affected. All DNS queries from our
> subscribers already redirected to our DNS cache servers. But seem Bind
> don't have feature to block MX query. Any best practice to block MX query?
> Regards
> Ibrahim



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