I have an issue where our websites will start erroring out for clients when they hit pages are required to be viewed over SSL. The "fix" is for me to go in on the Virtualmin Manage SSL Certificate page, go to the CA Certificate tab and click Save Certificate. I don't enter anything, I don't change anything, and the correct Certificate Authority information is showing, I just hit Save Certificate and the site starts working correctly immediately. We have two sites, both set to use full time SSL and both have this randomly occur.
This is logged in the Apache error log when the issue starts - [Mon Nov 30 03:29:13.903920 2015] [ssl:warn] [pid 10393] AH01909: RSA certificate configured for axxxxxxxxx.org:443 does NOT include an ID which matches the server name