On 31/12/22 17:29, Sean Hennessey wrote:
I'm doing some testing and am trying to figure out a way to set up postfix so that it won't ever send a DSN.
DSNs are an important part of email but if your server sends out too many of them, or in two many scenarios it becomes a potential source of backscatter*. I suspect that your actual problem is that your server is sending out backscatter and you want to stop it from doing so.
Unfortunately the approach you're taking will change your server from one that sends out backscatter to one that accepts mail and then ends up dropping it, which is arguably just as bad (but for different reasons). The correct approach is to instead try to fix your server's configuration so that instead of accepting mail and then sending out bounces in the case of invalid recipients, over quota, or just because of SPAM, that you instead configure your server to reject the mail as it is initially passed to the server. This means that you won't be a source of backscatter but you also won't be accepting mail and dropping it.
If this is really your issue then there are many people on this list (myself included) who would be happy to review your config and help you to fix it to avoid this problem in a much better way than dropping mail.
* https://en.wikipedia.org/wiki/Backscatter_(email) Peter
