Blocking MX query

[dot at dotat.at (Tony Finch)]

Ibrahim <ibrahim1 at gmail.com> wrote:
>
> We are thinking to block MX queries on our DNS server, so only spammer that
> use their own SMTP server will got affected. [...] Any best practice to
> block MX query?

Don't do this. It won't hinder spammers and it'll cause problems for legit
users.

Tony.
-- 
f.anthony.n.finch  <dot at dotat.at>  http://dotat.at/
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