Browse Tags using Distributed or Mirror Node Servers when Primary Server is Inactive

About this task

In a horizontally scaled system, there can be multiple Historian servers that are connected to one another. That is, if there are 100000 tags in your system, you can distribute them among the various servers. Similarly, you can view the tags and their values in all the servers.
For example, consider the following setup:

In general, the Historian configuration manager of the primary node stores the tag information of all the data stores in the system. Whenever a client machine requests tag information, the Historian configuration manager sends the corresponding information for all nodes (primary, distributed 1, and distributed 2) to the client machine through the client manager. Suppose the central configuration manager is inactive, in that case, the client manager of the primary node sends the tag information corresponding to the primary node (data store 1) to the client machine. Consequently, the tag information of the other nodes will not be sent to the client machine.

To overcome this, you can assign the other nodes as backups for the primary node's central configuration manager. Therefore, whenever the central configuration manager is inactive, the Data Archiver (DA) of the backup node functions as a configuration manager and sends all tag information to the client manager. The client manager will then forward the tag information response to the client machine. With this, you can still browse tags and their details when the primary node's configuration manager is inactive.

This topic describes how to set a distributed node as a backup node for the primary node.

Procedure

  1. Access Configuration Hub.
  2. In the NAVIGATION section, under the Configuration Hub plugin for Historian, expand Systems, and then select the system that you want to access.
    The selected system and its details appear.
  3. Expand the system to see the corresponding servers.
  4. Select a distributed node that you want to set as the backup.
    The selected distributed node's details appear in the DETAILS section.
  5. In the GENERAL section, enable Support for Browse Tags, if primary server down.
  6. In the upper-left corner, select save.
    The selected distributed node is set as a backup for the primary node's configuration manager.

What to do next

If your primary node's configuration manager is inactive, you can still browse the tags and their details corresponding to all the nodes within the horizontally scaled system.