Postfix – how to add emails to the queue without being delivered?

I have a quick question. How does one add emails to Postfix’s queue without it delivering the emails? I am writing a script to email Postfix statistics (queue count, sent, etc) to our support staff. I want to test it when there are emails in Postfix’s queue to see if its working correctly. However, every time I send an email from Postfix it gets delivered.

Thanks!

Some methods:

• Use @EightBitTony’s approach
• Use a VM for development and pull the virtual plug to the network
• Use a firewall rule to drop outgoing packets for port 25.

and the best way:

• How do I temporarily suspend mail delivery to a specific domain (non-local) with Postfix?

Check more discussion of this question.

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