Redirecting large amount of indexed links

I am in the process of launching 2 sites that have been recently redesigned (one in RoR and one in WordPress) they both have a very large amount of inbound links coming in from search engines and outside sources. This has been something I have been curious for quite some time on an efficient way to implement redirects on all links.

My main purpose of this is so the site does not lose the work it has done SEO wise and in addition not leave any old backlinks f开发者_开发技巧orwarding to a 404.

What is the best practice when launching a new site for redirecting old URIs?

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You'll find that most of your back-links are to your home-page anyway, so that will take care of the bulk of them. In terms of mitigating 404s from broken back-links, try to create a pattern-match (regex) redirect sending a 301 (Moved Permanently) header - using .htaccess (since you're using RoR/WP).

WordPress does have some plugins to handle migrations and redirections - simply search on the wordpress.org site.

Ensure you register your site with Google's Webmaster Tools and monitor your 404 pages (or log them server-side) to catch ones you've missed.

Lastly, to ensure that you get your new URLs indexed and canonicalization (beyond ensuring rel=canonical is used correctly), submit an XML sitemap of all your new pages.

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In terms of redirecting old links to new links, it is general practice to do a 301 redirect (for SEO purposes). In the absolute worst case you cannot do this, redirect to the homepage at the very least to not lose visitors to 404 pages.