Why old (301) links stay on Google when breaking site down to multiple domains

Question

Some background:

We did have single site and single domain (let's call it mainsite.com) with product information, however things have changed since and product database has grown fast. So we decided to move some major products/manufacturers under their own domains (let's call one of them subsite.com) while still using our main database/codebase.

What we've done:

Added subsite.com domain for product 1 by Great Products Co.

Some new nice looking front pages, info pages, etc.

Detail pages that will use information from original db.

Redirected product/group links from mainsite.com using 301 redirect.

Verified that redirects works as expected.

Waited some time for Google reindexing (over 30 days, I've heard it should be more than enough).

Results:

If I search our moved products from Google then it will found them and list them but with old links to our main page like mainsite.com/group/product1 but it should show link to new site subsite.com/product1. Links from Goole redirects as they should, as said redirects are verified [301].

Main question:

Any reasons why Google would not follow 301 redirects and update links so that they will point to our new mfg/product site subsite.com?

Answer 1

Have you checked (e.g. from webserver access logs) whether Googlebot has actually recrawled the old URLs yet? In my experience, Google can be really slow in recrawling existing pages, particularly if those pages haven't changed very often in the past and if they're not linked from many other pages.

Some things you could try, in order to get Google to recrawl the URLs, would be:

• If the number of moved URLs is fairly small, you could individually request a recrawl of each of them using the Fetch as Googlebot feature in Google Webmaster Tools.

• If there are too many URLs for that to be practical, you could try creating an XML sitemap listing those URLs (the old ones!), with <lastmod> timestamps corresponding to the time when the pages were moved, and submit the sitemap to Google. This should let Google know that the pages have been changed and prompt a recrawl, although it may still take a while.