Bug ID 1117637: FastL4 traffic traversing the tunnels such as VXLAN, may fail on VELOS and rSeries tenants

Last Modified: Mar 30, 2024

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

Known Affected Versions:
15.1.7,, 15.1.6,, 15.1.5,, 14.1.5,,,,,,, 14.1.4,, 14.1.3

Fixed In:
17.1.0, 15.1.8

Opened: Jun 21, 2022

Severity: 3-Major


The BIG-IP tenants running on an VELOS or rSeries system may incorrectly attempt to PVA accelerate traffic that goes through a VXLAN tunnel. That is, where the pool members are reachable through a VXLAN tunnel.


Connections fail. A packet capture from the F5OS layer shows packets arriving at the system, but not forwarded through the tunnel. As a result, packet retransmits are obeserved. A packet capture in the tenant shows packets arriving at the TMM, but with layer 3 and layer 4 headers rewritten to match the server-side connection information.


- BIG-IP tenant running on VELOS or rSeries. - Virtual server that processes traffic over a tunnel. For example, VXLAN, GRE, or IP-IP.


FastL4 acceleration is not supposed to work for traffic being load-balanced over a tunnel. To mitigate this issue, disable PVA acceleration in the FastL4 profile for virtual servers that will load-balance traffic over a tunnel.

Fix Information

Packets are successfully forwarded through the tunnel, these flows are not accelerated.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips