Redesign of site: structure, redirects and link text

[joergnw10]

I know there are some threads out there at the moment that deal with similar problems, but I have some specific questions and thought opening a new thread might be better.
I am changing my site from all html to a php database driven one as it is now just too difficult to keep updated doing all the changes by hand.
The site is the most successful one in its niche in all the main search engines and has been for over a year, so I’m very worried about the possible consequences of this change.
Most of my pages are indexed in Google, but about 98% are supplemental (don’t come up when I use site/example.com/*). Most of my hits from Google are directly to the homepage which probably also has about 98% of the inbound links.

1.Most of these 98% indexed (supplemental) pages are product pages which will look different and have some new content, but the old product descriptions etc will still be used. What is the best solution? Use a 301 redirect (for about 400 pages), use a 410 gone, or just a 404?
One of my worries is that if Google can’t find the old pages and does not index my new pages quickly enough (if at all) then a lot of internal links to the homepage would “get lost”, possibly harming the ranking of the homepage.

2. Should I use a 301 redirect for those 2% that are in the regular index and deliver some traffic from Google? In most cases it would be a redirect to a page with the same title and description, but the content would actually be different (i.e. before a list of products with links to these products, now pages with links to different product (sub-) pages).

3. If I should use a 301 that leads me to another question: I had a number of pages like this: one page for widgets up to £100 and one for widgets over £100.
Should I now redirect BOTH to the same product page?

4. How important is it that I keep the link texts & alt tags to the homepage in my internal links? They were quite varied in my old site but this would now be difficult for me to achieve. Should I rather change them to something like “Home” or should I choose a keyword/phrase that will be used throughout the site? Could Google regard the latter as spamming and penalize my homepage?

Thanks very much!

[BradleyT]

Just do it properly with 301's.

And I don't understand why you're concerned about losing all those links from your 98% of supplimental pages - those pages don't have any authority.

FWIW I'm doing the same thing right now and am not concerned because our site only ranks for branded company terms so having all internal pages change URLs shouldn't affect search engine referrals a whole lot because everyone enters from the homepage.

[tedster]

You can parse .html extension pages as php. That might help you retain some of the old urls (always a good idea). Many threads here discuss this approach, for example:

Parsing HTML as PHP [webmasterworld.com]

[joergnw10]

Thanks very much for your input!
So I'll do my 400 redirects, hoping it won't slow the thing down too much.
I will parse .html extension pages as php, unfortunately the url's can't be kept because this new listing program I'm using adds some characters and words that I can't get rid off as I don't know any php.
I have one more question, as I found out that there might be one potential problem:
When I delete listings the product page will not go 404 but will serve a 200 with a standard text like: 'This product is unavailable'. So eventually Google will think that I have a lot of url's that lead to the same content. Apparently it's not possible to change this. Is this something I need to worry about? If so, would it be sufficient if I added these url's to robots.txt?

[bwnbwn]

"When I delete listings the product page will not go 404 but will serve a 200 with a standard text like: 'This product is unavailable"

yes it is harmful as the SE's could index hundreds of these pages duplicate content and maybe be just enough dup to throw a filter and case the site much harm.

Is there anyway on this page you can have added a meta to not index as it will be just one page and should be able to add this in the meta tags this will keep the page from getting indexed and won't case any issues.

[joergnw10]

I don't think so. I don't know the technicalities behind this, but what it does is this: I add a product and a page will be created like www.example.com/listing-whateverItype-listing#
Whenever I type a url of this form into my browser and add a listing# that never existed or no longer exists it serves the same page (not available) and never a 404. I Don't really know where this page is created, but I asked the developers of this package and they said it couldn't be changed.
That's why my idea was to add the listings that are gone to robots.txt. Would this be sufficient to avoid the duplicate content issue?