Bug ID 777937: AWS ENA: packet drops due to bad checksum

Last Modified: Jul 12, 2023

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

Known Affected Versions:
14.1.0,,,,, 15.0.0

Fixed In:
15.1.0, 15.0.1,

Opened: Apr 29, 2019

Severity: 1-Blocking


-- Lower throughput and tps. -- High availability (HA) heartbeat is getting dropped, resulting in an active-active configuration.


Performance degradation and invalid HA configuration.


AWS Elastic Network Adapter (ENA) NIC is in use.


On the BIG-IP system, turn off checksum offloading in on TX as follows: modify sys db tm.tcpudptxchecksum value Software-only Important: This workaround negatively affects NICs other than ENA. Therefore, the workaround is recommended exclusively when ENA is the only dataplane NICs in use in the BIG-IP system.

Fix Information

AWS ENA: no packet drops due to bad checksum.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips