SFP ONU instead of a Rostelecom ONT: the stick doesn't register on the OLT and PPPoE won't come up
At home I've got Rostelecom fiber with the carrier's ONT installed, and I'd like to get the extra box out of the cabinet: plug an SFP ONU straight into the router and distribute it myself from there. I bought the stick, but I can't get past the first step.
- Keenetic Giga router, SFP port free
- Eltex NTU-SFP-100 stick
- SC/APC patch cord from the wall outlet, one meter
- in the area, apparently, a Huawei MA5683 OLT
What I'm seeing, collected in one block:
port link: up/down every few seconds
ONU on the OLT: not registered
PPPoE: session doesn't establish
stick housing after half an hour: about 80 C, can't hold it in your handTried:
- moved the stick to a MikroTik - same picture, no registration;
- checked the patch cord and cleaned the connector, no break;
- went through the PPPoE settings, same login and password that work fine on the stock ONT.
Am I right that without the carrier's involvement the stick won't come up at all, or is there still something to tweak on my end? And if the module does get activated, what should I expect regarding VLAN and IPTV?
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Comments 5
Short version: an SFP ONU isn't "a module instead of the ONT" - it's a full-blown terminal managed by the carrier. Until the stick's serial number is registered on the OLT, it doesn't exist for the network: no registration, no GEM ports issued, no point digging further.
Everything else arrives via OMCI from the carrier's side: GEM ports, CVLAN (with Rostelecom it's usually 10), profiles; some parameters get pulled in via TR-069. You can't set any of this by hand on the stick, there's simply no familiar ONT web UI there.
What to do: go to the carrier with the serial number and ask for registration as a subscriber terminal. Some will register it without argument, some flatly won't work with a third-party ONU - and then there are no options.
And about expectations right away, so there's no disappointment later. The sticks carry GEM transport fine, but bridge mode and multicast for IPTV only work if the corresponding profiles are set up on the OLT. If they don't provide them, you'll have internet but no IPTV. You weren't wrong about the 80 C, they really do run that hot, and overheating is exactly what causes those port flaps and speed drops. So airflow and a ventilated spot aren't a luxury, they're part of the installation.
First question that matters: did you give the stick's serial number to the carrier? Until it's entered on the OLT, nothing beyond "not registered" will happen - no PPPoE, no link in the usual sense. You yourself write "apparently" about the OLT - check with support to be sure, provisioning differs between Huawei and ZTE. Also say what firmware is currently on the stick and whether you tried another patch cord: some of these flaps get fixed by replacing the cord, not by settings. And check whether the port flaps with fiber plugged in, or does it jump the same way when the stick sits empty - those are two different stories.
Similar story, just different hardware: I ran GPON into an EdgeSwitch Fiber 12, with a Security Gateway behind it, instead of the stock HG8245XGC. I looked at the HPSP2120, SSX1LTC, and MA5671A. Same outcome - it all comes down to serial number registration, and to a direct question the provider answered that they likely won't accept a third-party ONU. Meanwhile a friend on MTS got a U Fiber Nano G working, with a Huawei OLT there and VLAN 30. One more thing people trip on: GPON needs SC/APC, the green connector. With a UPC patch cord you can spend a long time chasing a problem that doesn't exist.
I'll add something about picking a model. Carriers often have a short list of sticks they'll even agree to register: in some places it's D-Link DPN-100, Huawei MA5671A, Zyxel PMG3000, and Technicolor AFM0002/AFM0003, and anything outside the list isn't up for discussion. It's better to ask before buying, exactly like that: which ONUs do you register.
And the other half of the question is the host itself. On the hAP ax S the SFP port and LAN1 behave unstably, don't count on 800-900 Mbps there; if you need headroom, an RB5009 or a separate ONU ahead of the router makes more sense. On the PMG3000 separately: its IPv6 behavior changes from firmware to firmware.
All true, but it shouldn't be reduced to provisioning alone: the host can also be the culprit. On a Turris Omnia with Turris OS 5.0.3, an MA5671A with reflashed firmware HL23446 gets detected, but eth2 doesn't come up, and the log shows "SFP module encoding does not support 8b10b nor 64b66b". With the modified firmware the module also reports a transmit fault, with stock firmware it's an EEPROM read error.
Forcing the speed didn't help, nor did the branch with kernel 5.4 and its extra quirks. Meanwhile in the same router a DFP-34G-2C2 on a ZTE chipset came up calmly at 1Gbps/full, while a ZISA OP151S and G-010S-A didn't come up, the latter with an unknown compliance code. The same reflashed stick works on MikroTik if you set the speed manually. So some of these stories aren't about the OLT at all, but about how the host handles the SFP.