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Version: 2.6.4

MaestroHub 2.6.4 Release Notes

MaestroHub 2.6.4 is a maintenance release focused on OPC UA connection stability. It fixes an issue where abandoned OPC UA sessions could pile up on the server and eventually block new connections, and makes MaestroHub's sessions clearly identifiable in the server's diagnostics. Your pipelines, connectors and dashboards from 2.6.3 continue to work exactly as before.

What's Fixed in 2.6.4​

OPC UA​

  • No more leaked server sessions — Configuration updates, connection deletions and network interruptions could previously leave OPC UA sessions registered on the server without a client behind them. Each orphaned session occupied a server slot until it timed out, and on servers with a small session pool this could exhaust the limit and reject new connections with BadTooManySessions. MaestroHub now always closes the old session when a connection is reconfigured, stopped, suspended or deleted.

  • Sessions now identify themselves — MaestroHub sessions announce themselves on the server as maestrohub:<connection-id>:<replica-id>:<timestamp> together with a proper application name and URI, instead of the generic OPC UA library defaults. When you look at your server's session diagnostics you can now see at a glance which MaestroHub connection owns each session and when it was created.

  • Lower default session timeout — The default Session Timeout for new OPC UA connections is now 5 minutes (previously 60). MaestroHub touches a healthy session every 30 seconds, so active connections are unaffected — the shorter timeout only bounds how long the server keeps a session reserved after a network link dies.

    Good to know. Connections where you explicitly saved a Session Timeout value keep that value. If you have experienced session-limit errors, check your existing OPC UA connections and lower the setting to 5 minutes.

  • Fewer secure-channel renewals — An incorrect internal setting caused the secure channel to renew every few seconds on every OPC UA connection. This has been removed; channels now renew at the standard interval.

OPC DA and Redis​

  • Cleaner disconnects — The OPC DA and Redis connectors now fully tear down their subscription state on disconnect, preventing stray background activity after a connection is stopped.

Getting Started​

Download a native binary or pull the Docker image and follow the Getting Started guide to have MaestroHub running in minutes.