Thinking of installing this, but I'm wondering if there is a log / report of IP's which this ends up banning and if there is an "exclude" option.

Some web host configure these settings differently.

I would suspect the majority of vBulletin users are not all on VPS or Dedicated Servers and thus, do not have access to customize these settings.

what problem to answer me?!!!!!!!!!!!!!!!!!!!!!
its ok to vb 3.8.6 or not?!

The way this plug-in works. It maybe risky.

As this modification was developed for 4.x .... It would be risky to try it on 3.8

But if you're willing to backup everything and try it. I'm sure there would be others here who would like your feedback.

If the software blocks the bot at software level, robots.txt won't help you. I still suggest users use Google Webmaster Tools to monitor.

please explain more about any option in first post, with example
thanks

In the short time I've been a sysadmin my forum has come under a number of DoS and DDoS attacks, some of them quite large. I use CSF (a WHM frontend for iptables), but it's been my experience that fighting flooding attempts will quickly overwhelm even the best software. Blocking illegitimate traffic syphons memory and bandwidth from legitimate traffic. I guess what I'm saying is software is a poor substitute for hardware. Even an entry-level $200 Cisco device has smarter, more efficient packet filters. you'd be hard-pressed to find any datacentre that doesn't have a firewall. My advice to other sysadmins is software is great, bu you need a second line of defense. If you get attacked, it's your host's responsibility to block the traffic at their routers. They're capable of it in most cases and if they can't or won't do it, leave and find a better host.

Good stuff. I'll try it!

do you have this in English?

Dear Sir, Would you please make the setting for not to ban google boot for our site
Google ip ye de yazmak istersen
Google ip is 66**