Failed to send heartbeat ping to application process errors are being generated by the DX NetOps Spectrum Webtomcat Process

Products

• Network Observability

Issue/Introduction

User are noticing the below errors are being generated in the <SPECROOT>/webtomcat/logs/catalina.out file:

2026-05-01 04:06:50,796 ERROR [Webswing Process Handler] (AbstractSwingProcess.java:663) Creating thread dump...
2026-05-01 04:06:50,874 ERROR [Webswing Process Handler] (SwingProcessImpl.java:107) Failed to send heartbeat ping to application process oneclickwebapp_anonym_<session_ID>
java.io.IOException: Failed to write to application's input stream. The application oneclickwebapp_anonym_<session_ID> may not be responding.
2026-05-01 08:23:30,628 ERROR [Webswing Process Handler] (AbstractSwingProcess.java:663) Creating thread dump...
2026-05-01 08:23:30,688 ERROR [Webswing Process Handler] (SwingProcessImpl.java:107) Failed to send heartbeat ping to application process oneclickwebapp_anonym_<session_ID>
java.io.IOException: Failed to write to application's input stream. The application oneclickwebapp_anonym_<session_ID> may not be responding.

Are these errors indicative of an issue or are they safe to ignore?

Environment

All Supported Releases

Resolution

These errors are safe to ignore. They are benign race conditions that occur during normal session shutdown, not indicators of a system problem.

The Webswing framework (which runs Spectrum's OneClick web UI) spawns a JVM subprocess for each browser session and sends a heartbeat ping every 1,000ms to that subprocess. The Failed to send heartbeat ping error fires when the heartbeat timer happens to tick at the exact millisecond the subprocess's input stream has already been closed as part of shutdown.

The root cause in the full stack trace confirms this:

Caused by: java.io.IOException: Stream closed
  at java.lang.ProcessBuilder$NullOutputStream.write(ProcessBuilder.java:445)

NullOutputStream is what Java's ProcessBuilder returns once a process has already exited — the process was already dead when the heartbeat tried to write to it.