Canonical Tag - Double Checking Before Implementation

[Shark27]

1. I've recently discovered that a site I'm working on has LOTS of duplicate content. The dupe content is showing up in the SERPs and outranking the original pages which have the most links thrown at them. It's obviously not optimal to have different URL structures for the same pages and having them fight each other in Google.

The owner switched which URL he wanted to have and had no idea about the harmful SEO effects. As a result, there are many indexed pages of duplicate content due to the URL structure switch.

There are about 4 different versions of each URL that have been indexed.

Example:

example.com/product/kites/273
example.com/products/kites/273
example.com/product/kite-gear/273
example.com/store/kites/273

All of these are 100% identical pages. Each version of these pages contains links to dozens of other inner, deeper page links, causing even more duplicate content. Most of them aren't indexed, however.

Example:

example.com/product/kites/273/kite-strings
example.com/products/kites/273/kite-strings
example.com/product/kite-gear/273/kite-strings
example.com/store/kites/273/kite-strings

To properly implement a canonical tag, do I need to go to each of the pages using the structure I want to be the original/SERP result and insert the tag?

2. I have also just realized that the owner of the site has several clones on different domains which display everything the original has. The only difference between ANY of the sites is the domain name. The link structure, the page URLs, etc. everything is the exact same. Any update on the original gets immediately updated by the others and sometimes indexed before the original.

Will 301 redirecting all of these (between 4-8) to the original at once cause any SEO problems?

Thanks all. I greatly appreciate the help. I have read a lot about canonical tags and such, but most of the information I have found is from 2009 when the solution first came to light. I'd rather discuss it with knowledgeable SEO's before tinkering around on my own. Thanks again!

-Shark

[Shark27]

There were about 6 non-canonical URLs initially. All of these are 301'd to the canonical and the header plug-in tells me they're going to the canonical version in a single motion.

As a result of the 301 code, there's been a few new URLs created that we can't redirect. There's only been a single category that was indexed with this line of products so far. Each of those new URLs has the canonical properly placed within it. Any variation of that new URL automatically redirects to the version with the canonical in it. I don't expect any others to be indexed now.

[g1smd]

Sounds like you have most of the issues under wraps.

Test. Test. Test. And test again.

For one site I work on from time to time I have more than 2000 non-canonical test URLs of many different formats listed in a text file. I load that file into Xenu LinkSleuth and then check the results of a scan.

[Shark27]

I see. Sounds good. I'll definitely go through all of them and make sure they're tagged and/or redirected properly. Thanks a LOT for your help g1. I greatly appreciate it. You're the man!

[Shark27]

We recently dropped about 6 spots for all the main terms we were currently in the top 3 for (and some #1). Is this normal after 301'ing and using canonicals on a decent scale?

[g1smd]

It is certainly possible, especially if the URLs that were listed are now being redirected. It can take a few months for Google to catch up with things.

[Shark27]

Okay, cool. Just making sure it's normal for them to drop for a bit before coming back as strong (or hopefully stronger).

[Shark27]

So I have a list of all of the old URL structures this site used years ago. Many of them are still active and have PR. The problem is it's very difficult to figure out what these pages originally displayed so we can properly 301 them to their up to date canonical versions.

I've been provided with a listing of what each structure used to represent which definitely helps.

Right now it looks like this: www.example.com/blank/stores/3041/

So if I site: that in Google I get a list of each page within that URL that is still indexed (.com/blank/stores/3041/this-page.html). If there's no way to tell what these pages originally displayed, should I just redirect them to the closest thing I know of, which would be .com/blank/stores/3041/.

There are LOTS of these pages. Is it even worth individually checking on them or should we just 301 every old version to the canonical version of the main page now? Ex: Every page like this: .com/blank/stores/3041/random-page.html goes to current canonical URL of .com/blank/stores/3041/ or is that too much?

[g1smd]

I would not funnel multiple old URLs in a folder to a single new URL. I would keep it at a 1:1 or few:1 relationship.

Have you tried viewing the old URL over at archive.org too? You'll find most of your old content indexed there.

[Shark27]

That was going to be my next step. Unfortunately, there are tons of these and I'm not sure if it's worth it to do so. These pages won't compete in the SERPs with their new canonicals like the old ones have since they're not clone pages.

Some of them DO have PR so I think those are worth finding a sending over. It's unlikely any of these links are linked in enough places to receive click-through traffic and they go to the home page (mimicked, not redirected) anyway so that's not horrible.

Do you think it's worth going through and 301'ing the old links with PR to their proper pages SEO-wise?

[Shark27]

I've site: searched about 10 of the old structures and about 5 of them were indexed and had between 5-19 pages indexed each. None of them have PR and are currently indexed as a clone of the home page. I can likely archive.org them and find their original pages. Would you say this is the best way to go about this problem? And is it worth it in terms of SEO?

These pages probably receive close to zero click-through traffic, don't feature current content of any other pages (other than home page). The problem is for some reason sometimes these versions of pages show up in the SERPs for unrelated terms which can be quite annoying.

What's your honest opinion g1?