Ensure a reliable connection with hot-standby backup
For those systems that require an extra measure of protection, the Cogent DataHub supports hot-standby redundancy. Configure two identical data sources, and if one goes down, the DataHub will automatically switch to the other.
The DataHub Redundancy feature allows you to configure two ‘redundant’ input data sources, which typically are read through two separate OPC servers. If you want to, you can specify which of these data sources should be considered the primary data source if it is currently available. This will ensure the faster of the two redundant data streams is used whenever possible. Once the redundant data sources have been configured, you simple specify the name of a single output data domain with the DataHub. This output data domain is what the client program connects to in order to read data from the DataHub.
If data is available from either source domain, then the output domain (and therefore the client program) will receive live data. If the data stops arriving on the currently selected source domain, then the DataHub immediately switches over to use the other source domain. The client programs will not notice any delay and most time, depending on the update rate, no data will be lost.