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By Ben Bishop
Postfix is setup on my droplet where multiple domains (sites) are hosted. When sending some transactional emails from sites, they bounce to certain recipients though.
From the mail.log (redacted), “… (host mx.bt.lon5.cpcloud.co.uk[65.20.0.49] refused to talk to me: 521 smtpin48.bt.ext.cpcloud.co.uk Service not available - no PTR record for xxx.xxx.xxx.xxx)”
Now, my understanding is that you should only create single PTR records so am a little unsure of how to proceed?
I am aware of one option is to use an external service like Mandrill or SendGrid but would like to know what my options are for keeping my emails being sent from my droplet. Thanks!