[Sadu]

Say for example you are a SEO working with another web developer, and said web developer just made wholesale changes to the URLs on the live site. These changes were made inline with recommendations, but without due regard to 301 redirects from the old URLs.

This is a largeish site with good linkage, good traffic and probably good googlebot activity.

Say I wanted to keep Googlebot away for a few hours until I have got the URLs looking how I want them. Basically, there are now a gazillion different URLs for each page, the sitemap and main nav all pointing to different versions, so a massive duplicate content problem. I don't want Google to index all these "new" pages that will be getting deleted soon.

Any bright ideas for this?

I thought adding a meta nofollow tag sitewide to prevent Google from crawling the site this afternoon only, but the prospect of this is kinda scary. I definitely don't want to ward off the googlebot permanently.

The alternative is to just fix the problem soon as I can, and hope Google doesn't do a deep crawl in the next few hours.

Hmmmmm.