Multi Server CRM Upgrade Process

Create a manual backup of the database from the database server. For more information, see Overview of manual backups.
For all Sage CRM servers in the cluster, including the database server, create manual backups of the program files and the registry.
Set up a test environment that mimics the live environment as closely as possible. For example, if there are four servers in your multi-server cluster, set up four test servers, with each one an exact (or close) copy of a live server. For more information, see Performing a test upgrade.
Perform a test upgrade on the test environment.
Test the test upgrade.
When you're happy with the results of the test upgrade, perform a live upgrade on each Sage CRM server, starting with the database server. For more information, see Installing Sage CRM on the database server and Installing Sage CRM on a non-database server.
Test the live upgrade. For more information, see Testing a live upgrade.