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Server Groups Besides the general configuration concepts described in the "General Configuration Concepts" section above, the most important element in the domain.xml is the definition of Server Groups. Each AS instance is a member of a server group. (Even if the group only has a single server, the server is still a member of a group.) It is the responsibility of the domain management system to ensure that all servers in a server group have a consistent configuration. They should all be configured with the same profile and they should have the same deployment content deployed. The domain can have multiple server groups.