BugZero | F5 BugID 504280 - ZebOS daemons core on shutdown

F5 - Defect ID: 504280

ZebOS daemons core on shutdown - lack of good asynchronous handling of signals in ZebOS

F5 - Defect ID: 504280

ZebOS daemons core on shutdown - lack of good asynchronous handling of signals in ZebOS

Last updated on July 18th, 2026

BugZero Risk Score
6.9 Medium

Overall: 6.9

Severity: 7.3

Community: 4.2

Lifecycle: 8.3

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Bug Details

Priority: 3-Major
Status: Verified
Impact Category: TMOS

Description

Symptoms

A race condition between data structure initialization and clean up due to lack of asynchronous signal handling.

Impact

ZebOS daemons generate core files and might lead to false alarms and increased cost in dealing with the core files.

Conditions

Repeated shutdown and start of the ZebOS daemons.

Workaround

None

Fix Information

Provided support for Asynchronous signal handling of the ZebOS daemons. This enables a clean start and stop of the daemons.

Change history

Links

Original Vendor Announcement

Relevant Products

Click on a version to see all relevant bugs

Affected versions:11.5.1, 11.5.1 hf1, 11.5.1 hf2, 11.5.1 hf3, 11.5.1 hf4, 11.5.1 hf5, 11.5.1 hf6, 11.5.1 hf7, 11.5.1 hf8, 11.5.1 hf9, 11.5.1 hf10, 11.5.1 hf11, 11.5.2, 11.5.2 hf1, 11.5.3, 11.5.3 hf1, 11.5.3 hf2, 11.5.4, 11.5.4 hf1, 11.5.4 hf2, 11.5.4 hf3, 11.5.4 hf4, 11.5.5, 11.5.6, 11.5.7, 11.5.8, 11.5.9, 11.5.10, 15.0.0, 15.0.1, 15.0.1.1, 15.0.1.2, 15.0.1.3, 15.0.1.4

Fixed versions: 12.1.0, 12.0.0

Relevant Products

Click on a version to see all relevant bugs

Fixed versions: 12.1.0, 12.0.0

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F5 - Defect ID: 504280

ZebOS daemons core on shutdown - lack of good asynchronous handling of signals in ZebOS

F5 - Defect ID: 504280

ZebOS daemons core on shutdown - lack of good asynchronous handling of signals in ZebOS

Last updated on July 18th, 2026

BugZero Risk Score6.9 Medium

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

F5 - Defect ID: 504280

ZebOS daemons core on shutdown - lack of good asynchronous handling of signals in ZebOS

F5 - Defect ID: 504280

ZebOS daemons core on shutdown - lack of good asynchronous handling of signals in ZebOS

Last updated on July 18th, 2026

BugZero Risk Score6.9 Medium

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

BugZero Risk Score
6.9 Medium

BugZero Risk Score
6.9 Medium