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I want to test our secondary e-mail server but the primary one right now works correctly. How can I manage to make that server slow down a bit by using dns records and test the secondary server ?

Once at a time I did this by not writing the ns servers addresses correctly.

Do you know another approach ?

Thanks Baris

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MX records include a priority field. The smaller one is tried first. If they are equal, then they are tried at random.

However, I don't suggest you do it using DNS. If something goes wrong, it will take too long to fix, and you can affect your mail.

What I usually do is temporarily block incoming TCP port 25 from a specific client (usually one I control) and then test. This will let you test the mail servers but not affect production.

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+1 for blocking port 25 – James Jan 14 '10 at 11:25

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