I work at an internet service provider and we recently started using the ONT XX230V. However, we’ve noticed that in some cases—such as when a customer's power goes out or when they manually restart the device (not always)—the last character of the WAN MAC address changes.

This has been causing issues for us because we enforce MAC address control on PPPoE connections. When the MAC address changes, the device fails to authenticate, and the customer must contact our support team so we can recapture the new MAC address.

One device we tested was running firmware Build 240319. We’ve now updated it to Build 250423 and will conduct further testing. However, the firmware release notes didn’t mention anything about this issue.

Was this problem already known? Has it been addressed in the new firmware?

Notice in this image captured from our system that there was an active session (UP) with the MAC ending in 07:7D:3C, and a reboot was performed at 09:40. After 5 minutes of disconnection, we recaptured the MAC address of the connection, and the device connected with a MAC ending in 07:7D:3A. After two additional tests, the MAC did not change, but on the third test, it changed again to the previous one ending in 07:7D:3C.