It's good practice to always access the WordPress dashboard over SSL for security whenever possible.
We've been doing this in standalone WordPress for years, and in several WordPress MultiSite installs (directory-based) for over a year, with no issues at all. All updated to the latest version, and no issues at all.
However, we recently installed a new domain-based WordPress MultiSite, using the domain mapping plugin, and have several sub-sites running great on it, domain mapped. Been working great in production for over a month.
EXCEPT an odd issue with managing WordPress over SSL...
In the new domain-based MultiSite, if I'm logged in over SSL, WordPress seems to think that the actual public website is SSL too
For example, I create a new post, and at the top of the post edit page, it shows me the post Permalink as "https://".
I click Preview or "view post" and it opens the post with the https:// URL... SSL.
But in all our other WordPress installs, both standalone AND directory-based MultiSite, while of course still logged in over SSL, I go create a new post, and at the top of the post edit page it shows me the regular Permalink, i.e. "http:// "
So with directory-based MultiSite (or WordPress standalone), it doesn't get confused and think that suddenly the whole site is SSL just becasue I'm editing it over SSL. :-)
I've looked for others having this problem, and found this old support post was referring to a similar issue (rather a symptom of the same problem lol), but it's closed (though not resolved).
Does anyone have any idea why a domain-based MultiSite would be having this problem - confusing the production site as being SSL just because you're logged into the admin over SSL??