Bug ID 421586: fastl4 with immediate timeout causes L3 DSR traffic drop

Last Modified: Jun 19, 2025

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

Known Affected Versions:
11.1.0

Opened: May 21, 2013

Severity: 3-Major

Symptoms

Configuring fastl4 with immediate timeout causes L3 DSR traffic to drop. This is not observed with timeouts greater than 0.

Impact

Traffic is dropped.

Conditions

Fastl4 is configured with timeout 0 or 'immediate' in an L3 DSR scenario.

Workaround

Switch the timeout in fastl4 profile to greater than 0.

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips