Bug ID 985953: GRE Transparent Ethernet Bridging inner MAC overwrite

Last Modified: Sep 23, 2021

Bug Tracker

Affected Product:  See more info
BIG-IP TMOS(all modules)

Known Affected Versions:
14.1.0,,,,,, 14.1.2,,,,,,,,, 14.1.3,, 14.1.4,,,,, 15.0.0, 15.0.1,,,,, 15.1.0,,,,,, 15.1.1, 15.1.2,, 15.1.3,, 15.1.4, 16.0.0,, 16.0.1,,, 16.1.0

Opened: Jan 22, 2021
Severity: 4-Minor


Traffic not being collected by virtual server and therefore not being forwarded to the nodes.


Virtual server is not collecting decapsulated packets from the GRE Transparent Bridge tunnel unless the dest-mac of the encapsulated packet is the same as the mac-address of the GRE tunnel.


Encapsulated dest-mac is not equal to the Generic Routing Encapsulation (GRE) tunnel mac-address.



Fix Information


Behavior Change

Added a new DB key 'iptunnel.mac_overwrite'. This DB key defaults to 'disable'. To cause the BIG-IP system to overwrite the destination MAC of the encapsulated traffic, set the DB key to 'enable' and save the config: tmsh modify sys db iptunnel.mac_overwrite value enable tmsh save sys config This allows virtual servers on the BIG-IP system to process traffic.