Bug ID 712919: Removing an iRule from a Virtual Server may prevent executing other iRules on the same Virtual Server.

Last Modified: Jul 12, 2023

Affected Product(s):
BIG-IP LTM(all modules)

Known Affected Versions:
13.1.0, 13.1.0.1, 13.1.0.2, 13.1.0.3, 13.1.0.4, 13.1.0.5, 13.1.0.6, 13.1.0.7, 13.1.0.8, 13.1.1, 13.1.1.2, 13.1.1.3, 13.1.1.4, 13.1.1.5, 14.0.0, 14.0.0.1, 14.0.0.2, 14.0.0.3, 14.0.0.4, 14.0.0.5, 14.0.1, 14.1.0, 14.1.0.1, 14.1.0.2, 14.1.0.3, 14.1.0.5, 14.1.0.6, 14.1.2, 14.1.2.1, 14.1.2.2

Fixed In:
15.0.0, 14.1.2.3, 14.0.1.1, 13.1.3

Opened: Mar 30, 2018

Severity: 3-Major

Related Article: K54802336

Symptoms

When an iRule is removed from a Virtual Server, especially one with explicitly specified high priority (with 'priority' keyword), other iRules on the same Virtual Server may become 'invisible', i.e., they are present but some of them are no longer executed. It may affect all the events or only certain types of them. Under certain conditions the issue may even disappear upon removing another iRule, particularly if it has low priority and handles the same event as the one which introduced the problem.

Impact

Some or all iRules on given Virtual Servers stop being executed.

Conditions

Removing an iRule from a Virtual Server.

Workaround

Restart or reload the configuration. If removing iRules needs to be performed in run-time and it triggers the problem, you can prevent the issue by having any iRule (even an empty one) for the same event as the iRule which is going to be removed, but with higher priority e.g.. with attribute priority 1'.

Fix Information

Corrected scanning of iRules stored behind the one which is being deleted.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips