I have several sites in a /24
network that all get crawled by google on a pretty regular basis. Normally this is fine. However, when google starts crawling all the sites at the same time, the small set of servers that back this IP block can take a pretty big hit on load.
With google webmaster tools, you can rate limit the googlebot on a given domain, but I haven't found a way to limit the bot across an IP network yet. Anyone have experience with this? How did you fix it?