Site migration with duplicate content fix required urgently

[Whitey]

I've just uncovered an unsavory SEO blunder on some sites which has gone unnoticed and need some expert input.

Background:
A site migration took place around 2 months ago onto a new server. This site is configured to point all non www to www

A version of the old site exists on the old server, with the same content as the new site [due to be killed in the next 10 days]. It came into view under Google's site: command to show multiple non www. url's and sub domains such as webmail.mysite.com exist.

The old site interlinks to the new site. The new site is not linked to the old site.

An exact match of the content has it ranking higher than the new site.

So the old site needs to be gotten rid of asap. When a site has duplicate content on the same domain/ same server, I've seen sites restored in 14 days - but this is different as it is on 2 servers.

Question:
1. Is there a way to accelerate the purging of this duplicate domain content from Google's index urgently
2. How quickly will Google recognise the purging of the old site and restore the rankings of the new site which must be effected with results filtering by the duplicate

[ I don't want Google's index to take for ever to purge these urls ]. Any help would be appreciated.

[aakk9999]

So it appears that the new site was developed and put live without 301 redirects of the old site?
The best course of action is to do page-to-page redirect from URLs on the old site to the equivalent URL on the new site.

The reason for ranking of the new site not being good is probably greatly impacted by not having redirects from the old site.

What do you mean by "purging" from Google index?

[Whitey]

So it appears that the new site was developed and put live without 301 redirects of the old site?

The correct old site did have redirects put in place to the new site.

It's the duplicate old site's [ non www and subdomains ] that did not have the 301's put in place, because it was not known at the time that they existed.

What do you mean by "purging" from Google index?

The old site's non www. domain url's will be found in Google's index for as long as it takes for Google to crawl and remove them. By "purging" i meant, can the removal of those old url's be done. And accelerated. I hope that's clear.

[aakk9999]

It is clearer now :)

The fastest way is:
a) First verify these subdomains in Google Search Console (WMT)
b) Once verified, block each subdomain by robots.txt
c) Execute Remove URL in Search Console and remove each subdomain root
d) Once you see them removed, then you can switch off the site so that there is no DNS entry for the old site subdomains, so that they do not get added to the index again.

This is faster than just switching off the site as Google may think the site is switched off by mistake and may hold URLs in index for longer.

[Whitey]

@aakk9999 - thanks for those inputs.

My other concern is that there may be 100s of permutations not accounted for. How best is it to treat the unknowns.

[aakk9999]

I would say start with this and monitor what happens and then act on unknowns when they became known.

Note: If you just take the site down without removing it from index via Google Search Console, it will take much longer for it to disappear from the index.

[Whitey]

@aakk9999 - Thanks, we're making good progress.

My thinking is that two sets of redirects need to occur at some point in the sequence:

1. redirect all non www. versions on old server to www. on the new server
2. redirect all non legitimate sub domains on the old server to the legitimate sub domain on the new server

Some questions:
a) do you agree with the above?
b) if so, when in the procedure that you have recommended, would you slot this in?

[JS_Harris]

Suggestion: Place the page to page redirects ahead of the non-www to www redirects within your htaccess file. Then, for each page to page redirect, make them lead only to the www version on the new domain. Doing this will remove the need to redirect twice.

Making example.com/old-domain redirect to www.example.com/new-domain is more efficient than making example.com/old-domain redirect to example.com/new-domain and then redirecting again to add the www.