How many 301 Redirects via the .htaccess file are too many? And do I need to leave them in the .htaccess file indefinitely, or can I remove them once the new pages are indexed and get page rank?

How will this affect site performance if I have a large number of 301s?

I have a site with about 1500 pages that I want to completely restructure, and I want to use a different content management system, so all the URL structure will be completely different so I can't reuse any of the existing urls at all, most of which currently have a page rank of 3 or 4 and decent traffic. The current system also uses urls like /article112.html which i know isn't optimal for SEO, and this other CMS will give them names like /this_is_the_article_title.html.

I previously started to break this site out into subdomains, and everything I moved to the new subdomains immediately lost all page rank and most of their traffic, which it took several months to recover and the trafic is still down by a third. What is the best way to make this big transition?

Also, is it better to use subdomains or sub-directories to group related content? This is currently one big site about US indians with all the articles about all the tribes mixed together, and I am thinking it should be divided into sub-domains or sub directories by each tribe covered.

Any suggestions would be appreciated.

Leave them in fro 5-6 months, then check to make sure rankings have switched over and then kill them. I have never seen "too many" 301 redirects in the htaccess file. I have had 1000s.

If you already made the move then doing 301 redirects is probably to late. Even so you might want to still try. If you haven't then do what your suggesting put 301 redirects in place. This transition will always take time (3-4 months) so I always suggest to avoid it.

It doesn't matter which you choose. Think about what is best for your visitors, no the SE's here.

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