Hi,

I am using TX-6610 product on GPON FTTH Orange in France.

The device is operating fine on regular traffic.

However I would like to report a confirmed and probably complex bug related to the firmware.

my TX-6610 config under PON is "Transparent Mode", built-in DHCP is disabled.
Expected behavior is to work as pure bridge between my router and ISP network.

- The connection to the ISP is established through DHCP on a specific VLAN(832).

- Bug with TX-6610 : Initial DHCP request DISCOVER/OFFER/REQUEST/ACK (broadcast) is successful, however DHCP RENEWs (unicast) are failing most of the time (getting NAK reply from ISP / TX-6610). With ISP ONT (Huawei Echolife) instead of TX-6610, DHCP renews are reaching ISP and 100% successful.

- Workaround : telnet to TX-6610 and remove "hw_nat" module (rmmod hw_nat),  caveat is throughput very limited (300/300 instead of 800/500)

I suspect the firmware's hw_nat module (L2BRIDGE offload) to somehow interfere with DHCP packets between my router and ISP.
The situation is quite difficult to debug further as there is no opportunity to sniff packets on GPON side to see what might be missing or altered.

I would be happy to provide further output / testing to technical team.

Best regards,