Bug ID 2534861: FastL4 with late binding enabled, if the connection is offloaded to PVA, the connection may break

Last Modified: Oct 10, 2026

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

Known Affected Versions:
17.1.0, 17.1.0.1, 17.1.0.2, 17.1.0.3, 17.1.1, 17.1.1.1, 17.1.1.2, 17.1.1.3, 17.1.1.4, 17.1.2, 17.1.2.1, 17.1.2.2, 17.1.3, 17.1.3.1, 17.1.3.2, 17.1.3.4, 17.1.3.5, 17.5.1.9

Opened: Sep 24, 2026

Severity: 3-Major

Symptoms

FastL4 with late binding enabled, if the connection is offloaded to PVA, the connection may break if the client-side MSS does not match the server-side MSS

Impact

Connections/Transactions break

Conditions

- Virtual Server configuration: FastL4 Late binding enabled, with FIX profile - Hardware acceleration enabled; connection is offloaded to PVA - Client-side MSS does not match server-side MSS

Workaround

The Maximum Segment Size (MSS) Override option in the FastL4 profile can be used to override MSS value

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips