SEO Impact of Returning an Empty Response on HEAD Requests

I'm working a site that frequently gets floods of head requests from IPs in the Amazon cloud. I feel very confident based on the patterns that they access that they are up to no good. To combat this I'm considering returning an empty response on all HEAD requests, however I don't want to accidentall开发者_StackOverflow中文版y impact the rankings on this site.

Is anyone aware of search engines that legitimately use HEAD requests as part of the indexing process that might be affected by this change?

Hum,

Normally, if the ips you have spotted is not bots from search engines, they'll no impacts. If you have ban a big range of ips and with that legitimate users, you can have a bounce ratios to get higher and so it can theoretically impact your website seo performance. Odds are pretty small.

Nevertheless, the best implementation is to return a forbidden header ('HTTP/1.1 403 Forbidden'), it'll not draw ressources and it'll be cleaner.