I send out daily newsletters which contain links to my website. Directly after we send out a newsletter I can see a spike in requests to our website causing it to crash. After some investigation, I found that the spike in requests is caused by email clients scanning the links in the newsletter for security reasons, similar to how Gmail scans links to ensure they are safe.
Thus, the spike is not caused by real users clicking links on the newsletter and accessing the site.
Is there a simple way to block email link scanners from overloading our site, and are there any risks involved with using Super Bot Fight mode to try and do this?