Now, WordPress setting. As I had no experience about this, it was a worry to me, but, no problem. I found HOW TO do it.
I set “define(‘FORCE_SSL_LOGIN’, true);” in my wp-config.php. I don’t use “define(‘FORCE_SSL_ADMIN’, true);” because my server is already slow (^^;).
I access my log-in page. Immediately, I have a message “Multisite only works without the port number in the URL.”. OOPS!! I would have wanted to use port xxxxx instead of SSL well-known port. I have no choice, then I replace port xxxxx with the default. Well, I’ve got SSL login to my WordPress.
I must learn about rewrite rule or so. But now, I am satisfied by this level.