I ran into this devious issue when I had to change the base url for a demo site on which we are learning the features of the new magento. The site is running on an internal VM and I need to set a public access to it with a subdomain that is handled by an nginx proxy.
When I change the base_url store settings on the admin page after I save the page redirects then soon I receive an error message from the browser ERR_TOO_MANY_REDIRECTS. The frontend works fine but I can't reach the admin site.
I get the same result when I change setting directly in the db.
unsecure and secure urls are set correctly, use_secure_admin is turned off, I've tried cleaning the cache, turning it off, I turned off rewrites and I'm clearing the cookies as well. Nothing helped so far.
@kerdibCan you put more details like you have multi-website setup. In case of yes which is your default store. Where did you change the URL, Default or website level. For admin you would need to update the URL in default config.
Thanks for the reply.
This is a single store website. Now that you ask I might have only changed the website level config on the admin page, however I've got the same results by changing the base_url rows in core_config_data table which I'm pretty sure is the default.
Anyway we couldn't solve the problem yet but now we know the nginx proxy has something to do with it. Since we used a workaround and skip the proxy, the site seems to work perfectly.