Hello,

I have weird network issue with my ISP and in order to test if the issue is solvable with different OS, I installed OpenWRT 19.07.5 on my RB951G-2HnD, I made my tests and decided to rollback to mikrotik RouterOS using netinstall.

The issue I am facing is, that when I do the following:

1. Unplug the router from power
2. Hold the reset button
3. Plug the power cable
4. Wait for approximately 15 sec

The router starts sending DHCP discovery packets, I see them on the netinstall side, but the issue is that:
netinstall is replying with BOOTP responses, while the router expects DHCP (because that is what I set before flashing OpenWrt from menu: System --> Routerboard --> Settings -> Boot Protocol was set to DHCP.

I confirmed this with wireshark while inspected packets and also tested instead of netinstall to start simple DHCP server, and the router successfully accepted and set the IP in Etherboot mode.

So basically now I am unable to recover, because netinstall provides IP using BOOTP, which the router does not recognizes and expects for DHCP reply.

Can anyone tell me how can I revert back to BOOTP in Etherboot mode, considering the fact, that I have not RouterOS on the device.

Thank you.

I finally managed to flash using the following steps:

1. I borrowed ANOTHER router, same model.
2. Hooked to PC with netinstall started
3. While the router is Off, while holding the reset button, I powered the router on.
4. Waited around 15 seconds until the router boots from netinstall
5. Sniffed the TFTP transfer of the rescue image.
6. The router appeared in netinstall, but I dont need it anymore. Unplugged it.
7. Using wireshark File -> Export Objects -> TFTP I extracted the "rescue" image. This is the image, which is netbooted during netinstall, which makes mikrotik to appear in netinstall menu.
8. Started dnsmasq (which provides DHCP only and not BOOTP) and configured it to pass this file as boot.
9. With the broken router, execute the same steps as in 3 and 4
10. When the broken router boots, killed dnsmasq
11. Started netinstall under linux: ./netinstall -a 192.168.88.100 routeros-mipsbe-6.48.1.npk ( passed the same address as dnsmasq gave to the router)
12. netinstall saw the router and reinstalled it.
13. The router is back to MikroTik

For future reference, I had the same problem just now with a SXT Lite2. I messed around with OpenWRT, and now wanted to go back to RouterOS. But the bootloader needed DHCP so Netinstall wasn't working.

I don't have a spare device to do all those steps, so I installed the DHCP server from https://www.dhcpserver.de/cms/ and set it up to serve 192.168.88.1-192.168.88.254 on my Ethernet interface.
So when the SXT booted, it asked for an IP and got 192.168.88.3 (192.168.88.2 was my adapter's IP), and then it promptly showed up in Netinstall.

I *did* then have to close and re-open Netinstall before the installation succeeded.

However, now I have my SXT Lite2 back up and running RouterOS!

Thanks so much for your post, you put me on the right track.