idk who still has this issue, but i got a fix. here's what happened:
- 1. power outage knocks the building's gear offline.
- 2. a second router comes back holding the same gateway address as the real one.
- 3. devices find their gateway by broadcasting "who has this address?". the broken router answers, the working one doesn't.
- 4. every device in the building latches onto the dead router.
- 5. looks alive: you get an IP, you can ping it, the Wi-Fi bar is full.
- 6. it forwards nothing, so DNS fails first and everything reads as "connected, no internet."
- 7. reconnecting, rebooting, forgetting the network all re-run the same discovery and land on the same dead router, which is why nothing ever recovered on its own.
- 8. the fix: tell the device the working router's hardware address directly.
Source: r/uofm · by /u/LilDexterG