Bug ID 1104553: HTTP_REJECT processing can lead to zombie SPAWN flows piling up

Last Modified: Dec 07, 2023

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

Known Affected Versions:
15.1.5, 15.1.5.1, 15.1.6, 15.1.6.1

Fixed In:
17.1.1, 15.1.7

Opened: May 05, 2022

Severity: 3-Major

Symptoms

In the execution of a specific sequence of events, when TCL attempts to execute the non-existing event, it follows a path which in turn makes SPAWN flow to become a zombie, which pile up over time showing up on the monitoring system.

Impact

Clients may not be able to connect to the virtual server after a point in time.

Conditions

-- http2, client-ssl, optimized-caching filters on the virtual server -- HTTP::respond iRule with LB_FAILED event and set of iRules like HTTP_REQUEST, HTTP_RESPONSE, CLIENTSSL_HANDSHAKE, CACHE_RESPONSE, ASM_REQUEST_BLOCKING -- send http2 request through the virtual server

Workaround

None

Fix Information

This defect has been resolved and stale connections are being cleaned up as expected.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips