Not really. Postfix is very robust against attackers and knows to how to deal with bots by default. It makes sense to also configure SPF, DKIM and DMARC for your own safety.
If you want to stop the attackers from hammering, you can also add fail2ban.
If you want to avoid spam, you can attach a spamfilter to the delivery agent and let Sieve do the rest.
I’ve been running my postfix/dovecot combo using 4 mail domains for over 5 years without any problems. It’s simply fantastic.
JadedBlueEyes@programming.dev 7 months ago
I host mail via Stalwart, which makes it pretty damn easy - it handles most everything, just giving you a big block of DNS records to upload with all the DKIM SPF MTA-STS nonsense. However, spam filtering from big providers is still occasionally an issue. I still occasionally get reports of mail making it into Gmail’s spam inbox, for example.