About failover and load balancing

You can install two or more management servers that communicate with one database and configure them for failover or load balancing.
Load balancing occurs with a prioritized list of management servers that is assigned to a group. You should add at least two management servers to a site to automatically distribute the load among them. You can install more management servers than are required to handle your clients to protect against the failure of an individual management server. In a custom management server list, each server is assigned to a priority level. A client that comes onto the network selects a priority one server to connect to at random. If the first server it tries is unavailable and there are other priority one servers in the list, it randomly tries to connect to another. If no priority one servers are available, then the client tries to connect to one of the priority two servers in the list. This method of distributing client connections randomly distributes the client load among your management servers.
The following diagram shows components on different subnets. Management servers and database servers can be on the same subnets. The servers are identified with the numbers 1 and 2, which signify a failover configuration.
In a failover configuration, all clients send traffic to and receive traffic from server 1. If server 1 goes offline, all clients send traffic to and receive traffic from server 2 until server 1 comes back online. The database is illustrated as a remote installation, but it also can be installed on a computer that runs the
Symantec Endpoint Protection Manager
You may also want to consider failover for content updates, if you intend to use local servers. All the components that run LiveUpdate can also use a prioritized list of update sources. Your management servers can use a local LiveUpdate server and failover to LiveUpdate servers in other physical locations.
The use of internal LiveUpdate servers, Group Update Providers, and site replication does not provide load balancing functionality. You should not set up multiple sites for load balancing.
In 14.3 MPx and earlier, you can set up failover and load balancing if you use a Microsoft SQL Server database only. You can set up failover with the embedded database, but only if you use replication. When you use replication with an embedded database, Symantec recommends that you do not configure load balancing, as data inconsistency and loss may result.