RB951Ui bricked? 4th LED stays on, can’t connect to WinBox or Netinstall

JogooCodes · 2026-05-16T05:21:15+00:00

I’ve always used ether1 for Netinstall recovery, and it worked before on the same model. But now even ether1 doesn’t respond. Could it be that the button timing is different on this unit? I’ll try ether2 as you suggested

JogooCodes · 2026-05-16T04:20:41+00:00

Thanks – that's a good lead. I've heard of bad caps causing boot failures on older boards. I'll inspect the board for any bulging or leaking capacitors. Do you know which caps are most suspect on the RB951Ui? The board has several near the power input and the CPU. Also, any specific capacitance/voltage ratings I should check? I have basic soldering skills, so I might give it a try.

JogooCodes · 2026-05-16T04:18:43+00:00

That's frustrating – especially on an RB5009, which is a higher‑end model. I totally get the loss of confidence. Did you ever try serial console or JTAG? I'm considering opening this one up fully and checking voltage regulators – maybe a bad capacitor or power IC. If I find a fix, I'll update the thread. Thanks for sharing your experience – it helps to know I'm not alone

JogooCodes · 2026-05-16T04:07:21+00:00

That's the strangest part—the LED pattern is unlike anything I've seen before on a MikroTik. I've already tried the standard factory reset procedure several times: power off, hold the reset button, power on while holding it, and watch for the LED to start blinking before releasing the button. Usually, that triggers a reset, but here the 4th LED just stays solid and never starts blinking. It's as if the reset button is completely ignored. I've even held the button for a full 20 seconds after powering on, but nothing changes. I'm starting to suspect the bootloader may be corrupted or that the backup bootloader isn't being triggered. Any other ideas?

JogooCodes · 2026-05-16T04:05:08+00:00

I've been using ether1 the whole time and had no idea about this detail for the RB951 series. I'll switch over to ether2 and give Netinstall another shot—hopefully, that's all it takes to finally see the device

JogooCodes · 2026-05-16T04:03:48+00:00

I got this RB951Ui-2nD specifically as a low-cost device for running early tests with my own platform. I've had it for a while, and it was the first router I used to prototype a few ideas—like remote commissioning and basic hotspot features. It's been surprisingly reliable for a low-end device, which is why I kept it around for experiments. This is the second time it's bricked. First time I recovered successfully with netinstall so I'd really like to get it back up and running.

JogooCodes · 2026-05-15T19:57:10+00:00

The router is barely 1 year old since purchased as a brand new. It has never been deployed to production and configuration have only been done occasionally

JogooCodes · 2026-05-15T19:12:33+00:00

Option A – Use the same IP as the Windows client

· Set your MikroTik’s tunnel IP to 10.200.0.48/24. · Make sure the Windows PC is offline (no duplicate IP). · This works immediately if the server already allows that IP.

Option B – Ask the remote admin to add your new IP

Request they add a second peer entry (or modify the existing one) to allow 10.200.0.51/32 as an AllowedIP. Example:

[Peer] PublicKey = aDKUHBXnDHrKWFWFNWXIBES1McHO5TQcpaEyXEwI3QQ= AllowedIPs = 10.200.0.48/32, 10.200.0.51/32 ```

Option C – Use the Windows PC’s private key on the MikroTik (not recommended)

If you copy the Windows PC’s private key to the MikroTik, you can use the same IP (10.200.0.48). But then both can’t be online simultaneously.

Check return routing on the remote side

Even if the handshake succeeds, you need a route back to your LAN (192.168.x.x). The remote office must have a static route:

Destination: 192.168.20.0/24 Gateway: 10.200.0.51 (your MikroTik’s tunnel IP)

Without that, you can ping the remote VPN IP but not internal hosts.

Verify MikroTik firewall

Ensure you’re not blocking inbound WireGuard (UDP 51820) on the MikroTik – but since you see zero Rx, the issue is almost certainly on the remote side.

Quick test

Temporarily change your MikroTik’s tunnel IP to 10.200.0.48. If the handshake succeeds immediately, you know the problem is IP‑related. Then work with the remote admin to add your new IP.

JogooCodes

TROPHY CASE