MikroTik RB951G-2HnD stuck in boot loop

Installing and Using OpenWrt
1

Hi, I’m trying to install OpenWrt on a Mikrotik RB951G-2HnD.

I tried the flashing process from both RouterOS v7.20.5 and v6.49.19 and I also tried flashing both OpenWrt v24.10 and v23.05 (4 total tries).

In each try, I successfully load the init firmware image on the ram but when I try to fully install the firmware using the sysupgrade image from inside LuCi, my router gets stuck in a reboot loop even if I unplug it and power it up again so I use the netinstall-tool from mikrotik to format the hard and install a clean image of RouterOS.

Anybody else had this problem and can help me solve it?

I came across this topic when searching: https://forum.openwrt.org/t/cant-flash-mikrotik-rb951g-2hnd/72050 that suggests the NAND chip is different between specific models but I didn’t understand anything more from the dev talk and I’m not sure if this problem is also caused by the NAND chip being different (I don’t know which chip I have either).

I would really appreciate it if someone could guide me through on how to flash OpenWrt on my RB951G with a more simple way. (I’m not a total beginner but I’m also not an expert).

Thanks for your time!

2

that thread is really old, the change should be in the images since long, but it wasn't (I can't find it), so you have to compile your own image, assuming it's the same issue you're facing.

https://github.com/openwrt/openwrt/pull/17617 mentions the same flash chip, might be worth testing a snapshot image.

did you check your flash chip ?

3

I really don’t know if this is the problem or not.

How can I check my flash chip? Is there a software method or do I have to inspect the hardware for that?

4

you'll have to capture the boot log, which will require serial port access, meaning open the device anyway.

unless stock firmware prints the info, and you can read the boot log somewhere.

5

What's your Routerboot version?

6

Image 2025-12-17 at 17.57.47_6737eee4
Image 2025-12-17 at 17.57.47_6737eee4522×322 43.9 KB

I wonder if I can make up the chip type from the firmware type or serial number

7

Ok, I finally could boot on openwrt using the images found in: https://downloads.openwrt.org/releases/19.07.3/targets/ar71xx/mikrotik/

I initially booted nand-large-initramfs-kernel.bin on RAM, then used the sysupgrade command to install nand-large-squashfs-sysupgrade.bin

As you can see, the working image is under ‘ar71xx’ targets which is absent in versions newer than 19.07.9. In newer versions (21.02.0 and after), the mikrotik routerboards are now available in targets/ath79

I want to update the openwrt version currently installed but honestly I’m afraid that I would get stuck again and have to redo the whole process.

In the system status page of LuCI, it shows the architecture as: ‘Atheros AR9344 rev 3’. (Screenshot attached)
Can I upgrade my openwrt to a newer version? Or does this mean that the latest working openwrt version for me is 19.07.9?
If I can upgrade, to which version can I do so?

Screenshot 2026-01-02 161801
Screenshot 2026-01-02 1618011781×765 33.9 KB

8

Should be safe to update, as long as you don't keep the settings.

9

Hi, did you successfully update to OpenWrt?

I have similar, but not same problem. My HW is RB951Ui-2nD (hAP). I installed OpenWrt on multiple devices in the past, but they were all 6.xx firmware.

Now I got new boxes with 7.xx firmware. They were sitting in my office, because I followed this. But in the mean time mikrotik released new firmware where boot-loop should be fixed.

So I updated to 7.20.6, but no luck. I don’t get boot loop, but after I flash sysupgrade OpenWrt image, it boots back to RouterOS. I use 25.10.5

Anyone had any luck?