After years of running my own webservers and Mail-servers, I got annoyed by the amount of spam I had to handle and the almost daily task for it. But still I have to stop spam and after some googling I bumped into started using MX GuardDog.
So far I'm quite enthusiastic about the features MX GuardDog provides and the setup was easy.
Since I have some users on the VPS that are not really willing to pay an additional fee, I created a tiny change to the exim config
deny message = Email is handled by MXGuardDog - use the correct MX server according to DNS - https://www.mxguarddog.com/
domains = +protected_domains
!hosts = +relay_from_hosts
In the relay_from_hosts I've added the MX GuardDog MTA servers that deliver the mail and the protected_domains is configured at the header of the config file:
domainlist protected_domains = lsearch;/etc/mxguarddog_domains
So the content of /etc/mxguarddog_domains is for example:
example-domain-01.com another-domain.eu
So spammers cannot 'connect' directly via the VPS but need to use MX GuardDog
.
Another cool feature is that users within the domains can create an account theirselves and see the mail that is put in quarantine, release it and modify their preferences
