Quickly and efficiently migrating hundreds of servers from MySQL to MariaDB

Via SpamExperts:

SpamExperts has their own anti-spam filtering cloud which is provided as a software-as-a-service (SaaS) model. In addition they have an e-mail security product which they install, update and monitor on-site. Most of SpamExperts’ anti-spam technology has been developed in-house and makes extensive use of the MySQL database. All clients contribute in real-time to their filtering effectiveness, so they have many different data flows that are handled by MySQL. Replication is used to synchronize the data between the systems in a cluster and to push data feeds in real-time. The SaaS cloud is replicated across four countries for redundancy, whereas client installations spread the data retrieval around the globe.