URLs Case Sensitive Serving Duplications

[razasaeed]

At PakWheels.com we have URLs being generated in upper and lower cases. For example following URLs serve pages:

http://www.pakwheels.com/used-cars/search/-/mk_Toyota/

http://www.pakwheels.com/used-cars/search/-/mk_toyota/

Both show same content. Similarly in following four cases:

http://www.pakwheels.com/used-cars/search/-/mk_Toyota/md_corolla/

http://www.pakwheels.com/used-cars/search/-/mk_Toyota/md_Corolla/

http://www.pakwheels.com/used-cars/search/-/mk_toyota/md_Corolla/

http://www.pakwheels.com/used-cars/search/-/mk_toyota/md_corolla/

all of these 4 URLs serve page with same content. What is the best practice for this issue, is it generating duplication? Please advise

[TomRayner]

I think you're certainly looking at a duplication issue here.

Bearing in mind I don't know how your site generates pages, there's a couple of things you could do.  First of all, I can see that you have a rel=canonical system in place, which is a good start.  One option would be to choose the one version of the URL you'd wish to prioritise and then change the canonical on the other version to point to that page.  For example, you might want to change the canonical link on -> http://www.pakwheels.com/used-cars/search/-/mk_Toyota/md_Corolla/ to <rel="canonical" href:"<span="">http://www.pakwheels.com/used-cars/search/-/mk_Toyota/md_Corolla/"></rel="canonical">

Alternatively, and what I'd recommend, would be to 301 redirect the URLs to your preferred address, as the pages are serving no extra purpose for the user.  Implementing a 301 will stop Google from crawling those pages and therefore flagging up any duplicate content issue.