How to disable bounce emails in exim ?
I don't want the server to send a bounce message when the email not exists.
Bounce is sent when message can't be delivered - i.e. there is no appropriate router for delivery. If you definitely sure you want to drop all messages for non-existent recipients, you have to add the very last router:
dropper: driver = accept transport = null_transport no_more
But I'm not sure it's a wise choice. If someone do a typo in the legal address he will never knows about it.
Way better is to check recipients at the RCPT stage in the ACL.
You can do that this way:
acl_rcpt: . . . . . require domains = +relay_to_domains : +local_domains verify = recipient . . . . .
If incoming message have recipient doesn't listed in your user-DB, that message will be denied to submit. The only minus of that approach is that you have to be familiar enough with
exim's ACL, as far as that rule should be placed in the proper place within ACL.