I remember having a friend with an extemely sluggish server. Turns out the reason behind this sluggishness was that he set a permanent fail2ban bantime, which a

I remember having a friend with an extemely sluggish server. Turns out the reason behind this sluggishness was that he set a permanent fail2ban bantime, which added thousands of records to iptabes; any packet, even not SSH, the server had to check the source IP against thousands of records. After purging the rules and switching the bantime the server was usable again.