Hi all,
I’m having a persistent WAN link flapping / disconnecting issue with a GL-MT6000 (Flint 2) when used directly with Sky Broadband FTTP in Ireland, and I’m hoping someone here (or GL.iNet staff) can advise.
Setup
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ISP: Sky FTTP (Ireland)
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ONT: Sky-provided fibre ONT
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Router: GL.iNet GL-MT6000 (Flint 2)
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Connection: ONT - Flint 2 (tested both dedicated WAN and WAN/LAN1)
behaviours
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WAN Ethernet continuously flaps (connect / disconnect)
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PPPoE never completes because the physical link is unstable
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This happens:
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With a clean config
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With PPPoE (sky / sky, MTU 1492)
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With and without MAC cloning
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On both WAN ports
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After full ONT power cycles (5–15 mins)
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Plugging the Sky router back into the ONT works perfectly. Power and PON LEDs on the ONT are solid green This strongly suggests the fibre line and ONT are healthy
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PPPoE credentials (are these correct in Ireland)
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Cabling (multiple known-good Cat6 cables tested)
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Multi-WAN / failover
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MAC binding (Sky router MAC cloned successfully)
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Firmware reset / clean setup
Both WAN ports on the Flint 2 negotiate at 2.5 Gbps, and there appears to be no way to force 1 Gbps on the WAN interface.
It looks like a PHY / auto-negotiation compatibility issue between the Sky ONT and the Flint 2 Ethernet chipset.
does anyone know:
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Is this a known interoperability issue between the GL-MT6000 (2.5G WAN) and certain Sky/Openreach ONTs?
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Is there any supported way (UI, LuCI, or CLI) to force the WAN port to 1 Gbps Full Duplex on the MT6000?
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Has anyone successfully used a Flint 2 directly on Sky FTTP Ireland without placing the Sky router in front?
