The reason being is that we have vendor support for MS platform and tools that would enable HA features on MS SQL-Server, which we don't have on MySQL at the moment.
Current design is:
- RHEL 6.6 64-bit with 16GB of ram. PHP 5.6.26. MySQL 5.5 community. Moodle 3.2.7+ (will go to 3.4 in August).
- OS and Moodle and DB engine on same VM server.
- DB files are on a network drive actually.
- moodledata files are on a fileshare.
I recommended still to go with MySQL but with enterprise version and re-architect it to have a separate DB server with at least 32GB of RAM. I would make the moodle server 32 GB of ram as well.
What I have not figured out yet is:
- How to set up failover and HA best platform configuration and options in a Linux platform.
- Where and the best setup for /moodledata folder.
We expect a huge amount of concurrent users to the platform and while our current platform is fine, we want it to be better supported, more formalizes, enterprise-ready, scaleable, and do it right once the first time ready for growth if we need it.