There are a ton of questions asked on Multisite domain mapping but none I can find with an answer that works for me. I am using subdirectories. Here is my configuration:
(1) Root non-www: mysite.com (works - non-www by default)
(2) Root www: www.mysite.com (works - redirects to mysite.com)
(3) Subsite www: www.mysite.com/subsite (works - www by default)
(4) Subs non-www: mysite.com/subsite (broken - redirects to 404 error)
I have tried adding code in .htaccess and in wp-config.php. Either way I can fix (4) but this creates an indefinite loop in the root site, breaking (1) and/or (2). This is because the root is non-www and the subsites are www. Is there a conditional statement for .htaccess that can fix this? Or is it better to address domain mapping via wp-config.php?
I also looked at the MU Domain Mapping plugin, but it asks subsite-users to set-up a DNS ANAME or CNAME. This is too complicated for my users - the redirect needs to be automatic.
Any suggestions would be much appreciated.