This tutorial describes the installation of a clustered web, email, database and DNS server to be used for redundancy, high availability and load balancing on Debian 6 with the ISPConfig 3 control panel. MySQL Master/Master replication will be used to replicate the MySQL client databases between the servers and Unison will be used to Sync the /var/www (websites) and /var/vmail (email account data) folders.
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