Overview of changes to the known servers table (KST)

This topic provides an overview of the changes to the known servers table (KST) for PI AF Client 2024. It also explains how to ensure your servers are properly recognized across AF SDK-based and PI SDK-based applications.

Note: The new file-based KST is located at C:\ProgramData\OSIsoft\AF\PIDataArchiveKST.config. Manual editing of the file is discouraged.

• During upgrade to PI AF Client 2024:

  When you upgrade to PI AF Client 2024, any existing PI Servers in the registry-based KST are replicated to the new file-based KST for AF SDK applications.

• Post-upgrade considerations:

  After the initial replication during upgrade, the registry-based KST and file-based KST are not automatically synchronized. Therefore, any new servers added after the upgrade must be manually added to both the AF SDK and PI SDK environments to ensure full accessibility.

  For more information, see Migrate the KST using PI Server tools.

• Adding new Data Archives:

  • AF SDK-based tools: Adding a new Data Archive through the Connection dialog in an AF SDK-based PI Client (for example, PI DataLink) makes the server visible in other AF SDK tools, such as PI System Explorer and PI Web API.

  • PI SDK-based tools: Adding a new Data Archive through an AF SDK-based PI Client does not make it visible in PI SDK-based tools (for example, PI Buffering Manager). In this case, the server must be added separately to the registry-based KST to ensure it is available in those tools.

    For details on KST access methods, see KST access methods in PI Server products.