PoE注入器LAN口直连引发Ubiquiti Nanostation Loco M2频繁断连的故障排查咨询
Hey there, let's break down what's going on with your Loco M2 setup—this is a classic misconfiguration pitfall with PoE gear, and your LAN-port direct connect is almost certainly the root cause.
First off: connecting the LAN ports of two PoE injectors directly to each other is a big no-no. Here's why: PoE injectors are built to pass power + data from a network switch/router (their "IN" port) to the PoE device (their "OUT" port). When you cross-connect two injectors' LAN ports, you're creating conflicting power loops and messing up the Ethernet PHY chip negotiation on both Loco M2s.
That explains all the weird behavior you're seeing:
- The power and LAN LEDs stay on because the devices are still receiving power, but the data link is stuck in a constant cycle of partial negotiation (hence the split-second "connected" blips on your switch) and failure.
- The PHY chips on the Loco M2s are probably being hammered by this conflicting setup—they aren't burned out (which is why you don't see visible damage), but they've entered an unstable state where they can't maintain a reliable data connection, even after a factory reset.
Let's walk through the fix and verification steps:
Fix the physical setup immediately
Ditch the direct LAN-to-LAN injector connection entirely. The correct chain should be:- Main network router/switch → PoE injector (Data/Power IN port) → PoE injector (PoE/Data OUT port) → Loco M2 LAN port
- Set one Loco M2 as Station mode to connect to your main WiFi
- Set the other as AP mode, and wire its PoE injector back to your main router/switch (not the other injector)
Test each device individually
Disconnect one Loco M2 at a time, hook it up to a working PoE injector and your main switch, then:- Try pinging its default IP (192.168.1.20 is the factory default for Loco M2s)
- Check if it stays connected in your switch's GUI for at least 5-10 minutes
If one device works and the other doesn't, the problematic unit might have sustained subtle damage to its Ethernet PHY from the bad setup.
Do a full, clean factory reset (again)
Sometimes a quick reset doesn't clear the wonky state from the bad connection. For each Loco M2:- Hold the reset button for 15-20 seconds (until the LEDs flash rapidly)
- Let it fully reboot, then reconfigure it from scratch (don't restore any old configs)
Swap out the PoE injectors
Your existing injectors might have taken a hit from the direct connection too. Grab two known-good 24V PoE injectors (the voltage Loco M2s require) and test the setup again with those.
If you follow these steps, you should be able to get your Loco M2s stable again. The key takeaway here is that PoE injectors aren't meant to be daisy-chained or cross-connected directly—they need to be part of a proper network topology with a switch/router in the middle.
备注：内容来源于stack exchange，提问作者motaha
