Hello, our mail server is being target by a botnet, and would appreciate any tips you can give in relation to this, we have set the fail2ban max attempts to only 3 with a retry window of one year, and a ban time of also one year, a bit extreme I know, but we are a small company with 6 people, and if one of our ip gets banned, I can just unban, what else I can do to prevent this? is there a way to ban ip’s from outside our country since we don’t need to connected from other regions, also, whitelisting only our ip’s would not be beneficial, because we have an application in our client’s that uses one of our mail to send backup reports to itself it has the effect of us connecting from multiple ip’s from our region, but that account has rspamd rules that prevents it from sending any mail to any other account, I would like you opinions, and thank you for having the time to read this post 😊