Update:
I noticed an sql error on a duplicate key when adding a fresh domain page. I had previously deleted three pages with three different domain names.
Looking at the mysql table wp_pronamic_domain_posts, that still had the records to those three pages.
So: deleting the pages, didn’t delete them from that table; adding a new page (which uses one of those three previous domains) somehow created the page, (in another table?) but did not got updated in the wp_pronamic_domain_posts (the post_id was still an old reference).
I now manually emptied the wp_pronamic_domain_posts table – and had no pages defined by the wp-admin backend. I then created a new product.com page. I’m still getting the 301 redirect loop though.
(BTW: I test that with curl, as the browser often caches old redirects)
