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We have a Magento store, with multiple stores/domains setup. There is only really one reason that we have the multiple domains; we use an automatic GEOIP store switcher to send a customer to the right store, so that they pay the proper shipping, see the proper pricing etc, and a couple small differences in the design templates. But all the content is identical. So we have: domain.com (main website)
domain.ca (where most other countries are directed to based on GEOIP)
domain.eu Since the content is the same, what is the best strategy here? I looked at several options: 1. Custom canonical urls, making each page on the .ca and .eu use canonical url of the .com
2. Completely block the .ca and .eu from robots.
3. Leave it the way it is