Operating system: Centos
OS version: 8
I’m setting up virtualmin for the first time. I have 3 domains and I’m the only user. I have several email aliases and most forward to my gmail account. I have one account that gmail accesses via pop3.
For each alias, in gmail, I must setup the SMTP to point to my SMTP server. There is a place to indicate the authentication credentials.
Does it matter if I use the same credentials for all the aliases? or should I use the credential associated with each domain account?
Also, I’m trying my best to make sure everything is secure.
I’m trying to determine the minimum number of ports I need the firewall the let through. I understand I must have port 25 open to receive email. 995 for POP3 TLS/SSL. For outgoing SMTP, do I need 587 for TLS or will it work over 25?
I’d be interested in what else I can do to protect my email (and apache) server from attacks.