Redirecting old pages of asp.net webiste to new pages of new website designed

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http://serverfault.com – I have a website in asp.net, and about 27,000 pages of its are indexed in Google. I want to redirect all the pages of this site to the new site that i have made in the same platform. The problem is, if i started redirecting the pages manually, i.e. for each page it will take months and not possible for me. Could someone help me out of this if some logic can be implemented to sort it out, so that all old pages will be redirected automatically to the particular new dedicated pages. (HowTos)