Static to Dynamic site redesign and content redirects

[webharvest]

I'm designing a new site using a temporary domain name. The new site will be dynamic where the old site is static. Making the big change from asp to php!!!!!

I have very high rankings now and I don't want to change that. The content isn't going to change much since I plan to bring the actual content over but the page names are going to change dramatically.

What is the best thing to do to insure that my rankings don't go down the tubes?

Thanks

[hostBrain]

This should work.
You'll have to replace content of the old pages, with the following code

<%@ Language=VBScript %>
<%
Response.Status="301 Moved Permanently"
Response.AddHeader "Location", "http://www.newsite.com/new-site.php"
%>

[bj]

You may have to do a 301 for each old page name to its corresponding new page name. If there is rhyme and reason to the new pagenames it's possible someone here can write up an htaccess magic gizmo to "transform" them, but we'd need to know what the URL structure is, both old and new. And if the file logic is changing you might have to 301 each and every single page.

[Orion]

Most of the time we've done similar ... updating a site with new coding page file name changes etc. we've 301'd all the pages...

9 times out of 10 rankings fell (TEMPORARILY) before coming back hire than before.

offset temporarily by doing a bit of or increasing PPC if needed...

Probable reason for temporary fall and how to get rankings back....

LINKS (IBLs) .. All the IBLs for the site go to the existing (old) pages... you need to contact the holders of those links to get links to the new pages..

and

add a few more new links and expand the content on the site a bit

make sure you update your google and yahoo site maps as well as your HTML sitemaps
don't forget to update your robots.txt file too!

... just another 2cents worth... =o)

[rwil02]

Try considering using url_mod_rewrite to map all .asp file requests to their real .php equivalent in the background.

That way all your existing links, etc will work transparently, no SEO issue at all.

Then you need to consider if/how you go about introducing the new pages

[webharvest]

Thanks for all the great input. I fell away for a few days. Man this is going to be some work

The old site has about 500 to 600 pages easy.

I like rwil02 idea about the url_mod_rewrite but does the SE not like to see the rewrites and penelize you. As far as the new php pages go when the site gets pinged again the sitemap should take care of introducing the new pages. I guess the problem will be that the SE won't put together the IBL to my new pages and not give me a high ranking.

James