So I have set up my own mail server 🙃 🙂. What an achievement for me 😆😅 And it was working fine till recently. It becomes really, really slow. And I checked the log and found out this. What could I do and what’s the purpose of this? Is it a brute force attack? All these ips are owned by the same person/group?? Any help or pointers will be deeply appreciated
A quick search for one of the IPs shows this: https://www.abuseipdb.com/check/46.148.40.161
So yes, it’s most likely an attack.