Chapter 6 Working with network distributed applications
Rockwell Automation Publication VIEWSE-UM006K-EN-E
Deciding when to use multiple servers
A network distributed application does not require more than one HMI server
or data server, but there are circumstances, in which it is helpful to use
additional servers. For example, you can add servers:
To set up redundancy for HMI servers or data servers.
To let different integrators work on different HMI servers, without
worrying about name collisions or having to integrate all the project
Adding servers for redundant operation
To provide secondary application servers in the event that the primary
servers goes out of service, set up redundant HMI servers and data servers.
Tip: If you plan to deploy a network distributed application
that uses more than two servers (or two pairs of
redundant servers) and 20 clients, or if you would like
architectural assistance, contact your local Rockwell
Automation Sales office for architectural assistance .
For information about setting up redundant FactoryTalk
View SE Servers, see Setting up FactoryTalk system
availability on page 349.
You must set up redundancy separately for each server in an application. For
more information, see Setting up FactoryTalk system availability on page
Adding servers for load balancing
Over time, an HMI project might increase in size, or the number of clients
connecting to an HMI server or data server might increase to the point where
the computer running the server becomes overloaded.
To balance the load, install another HMI server or data server on a separate
computer, and then move some of the HMI project components, or some of
the OPC server tags, to the new server. This distributes processing more
effectively across computers.
Running multiple HMI servers
Each area in a network distributed application can contain only one HMI
When deploying a network distributed application for production, ensure that
there are no more than two HMI servers running on each host computer. If
the HMI servers are primary and secondary partners in a redundant pair, only
one server per computer is permitted.