Troubleshooting Session Heartbeat Failure after Workbench Upgrade

Workbench
Kubernetes
Positron
VS Code
upgrade
Published

January 29, 2026

Abstract

Resolving status bar errors in Positron and VS Code sessions caused by heartbeat failures after upgrading Posit Workbench to the Apple Blossom release, or later.

Description

When upgrading Workbench from a version prior to the Apple Blossom release to Apple Blossom or later users may see errors in the status bar of Positron and VS Code sessions indicating that the session’s heartbeat to Posit Workbench has failed. The heartbeat failure in Positron and VS Code sessions shows as a red status bar:

A screenshot of the Posit Workbench home button in the Positron IDE status bar. The bar is red and displays the error 'Heartbeat failure'. A tooltip of the status bar error reads: 'Error sending heartbeat: session will terminate soon...'

Positron heartbeat failure

A screenshot of the VS Code IDE status bar. The bar is red and displays an error message indicating that the session heartbeat has failed. A tooltip of the status bar error reads: 'Error sending heartbeat: session will terminate soon...'

VS Code heartbeat failure

Background information

The heartbeat is how sessions report to Workbench that the session is actively being used. When the session goes idle (or if the heartbeat fails to send) this indicates to Workbench that the session should be terminated to free up system resources. See the Positron or VS Code idle session timeout sections in the Workbench Admin Guide for more information.

Apple Blossom includes changes to the method sessions use to communicate with Workbench. In this scenario where:

  1. A session was started in Kubernetes with a Workbench version prior to Apple Blossom, and
  2. Workbench was upgraded to Apple Blossom (or later) without first shutting down all sessions

The session continues to utilize the legacy backend communication with Workbench which is no longer considered valid by Workbench.

Solution

To resolve this issue simply close the affected Positron or VS Code session and start a new session.

The new session will be launched using the updated session communication protocol compatible with the Apple Blossom release of Posit Workbench.

To avoid upgrade scenarios like this always remember to shut down or suspend all sessions before upgrading Workbench. See Workbench Upgrade procedures in the Workbench Admin Guide for more information.

If you’re still having issues, you can reach out to Support by opening a ticket.