I thought the last attack was over. The joining security was at low. When the attack started I raised it to medium and then to high. Yesterday I thought I would try medium again. That was the wrong decision. I have now increased the security back to high. With the high security it stops the robots joing, but also makes it hard for real people to join.
I have banned two complete IP addresses. One in Saudi Arabia, I think the other is Czech. They are trying time and time again to join. My error log is showing them trying about 40-50 times a day.