@hariselio I couldn't spend much time on this after this. I get a feeling that the firmware of the
ZyXEL unit that I have, is not respecting changes to the
GPON SN. In the UI it shows that the serial has changed, but in reality it doesn't seem to be changed.
When I tried on BSNL, it got stuck in O2/O3 state ie serial number verification stage. In case of Airtel, it went to O5, but I think AIrtel does fake O5. I intended to flash a newer firmware, and see if it helps, but didn't get time for it.
The other
Huawei GPON SFP I got, need serial console access to root it and enable telnet/shell.
How much was the ODI DFP-34X-2C2 including delivery, where did you get it from? I had reached out to a reseller of DFP-34X-2C2, said it is some 28 USD/unit (before shipping/customs).