Magento multi-domain checkout issues

Question

I have a Magento install with multiple domains (domain1.com, domain2.com) sharing a single checkout URL (checkoutdomain.com). The problem is when I proceed to cart and do to the new domain I get "no items in shopping cart" error. For some reason the session/cookies aren't being passed to the checkout domain.

I'm running Magento 1.7. I've gone to system/config/web/session cookie management and tried all of the following values in the cookie domain field:

.domain.com
.domain.com/
http://www.domain.com
http://www.domain.com

Should something else go here?

I also have cookie path field blank (default) and use http only set to yes (default).

I'm not sure what else to do here.

Answer 1

The first place I'd check is your store setup. Remember that you can't easily share a cart across multiple Websites, only Stores and Store Views (to use Magento's nomenclature).

Assuming that's fine, your next problem is ensuring that all of the domains use the same PHP session. You can do this by telling them all to use the same session id. Cookies are an ideal solution for this, but cookies do not work across completely different domains.

This means we have to explicitly tell checkoutdomain.com to session that we wish to load. We can force Magento to load a specific session by passing the session id as the SID GET parameter. You can get this value by calling Mage::getModel("core/session")->getEncryptedSessionId().

Answer 2

You should set web/session/use_frontend_sid to yes in your system configuration.

Answer 3

You should also keep in mind that not specifying a cookie path will make it default to the current path you are on when the cookie is set. You should default it to "/" to make sure it is being set globally for the site.