Last Modified: Jul 29, 2026
Affected Product(s):
BIG-IP All
Known Affected Versions:
17.5.1.3, 17.5.1.4, 17.5.1.5, 17.5.1.6
Fixed In:
21.1.0.1, 21.0.0.3, 17.5.1.8, 17.1.3.4
Opened: Feb 27, 2026 Severity: 3-Major
Middleware runtime statistics are unavailable in production builds because middleware tmstat instrumentation is only enabled in debug builds
Reduced diagnosability for engineering and support teams, as middleware runtime statistics used for debugging and troubleshooting are unavailable in production builds. There is no impact on customer traffic handling or feature functionality
Running a production (non-debug) TMM build and attempting to inspect middleware runtime statistics for troubleshooting or post-incident analysis is not possible
Use a debug build with middleware tmstat instrumentation enabled
Middleware tmstat instrumentation is now enabled in production builds, providing access to middleware runtime statistics for troubleshooting and post-incident analysis while preserving existing functionality