Help installing OpenWrt on Mikrotik RouterOS/board, RB750GR3

I need help installing OpenWRT on a Mikrotik routerboard. It’s a hEX series RB750Gr3. I read the instructions on the installation page but I don’t know how to boot from the network in Fedora 32. Also, I would really appreciate step by step instructions in detail that won’t let me screw this up. Thank you in advance.

Have you looked the following page in the wiki?

You can follow a generic tutorial to get a TFTP server installed such as

Dear Andreas,

Thank you for your response. I know that they provided detailed directions but I don’t really understand how to implement them. Could you provide clarification about how to set up the servers to netboot with Openwrt? For example, under Common Procedures on the Openwrt Directions page, it says,

Pre-requisites. First, save the license key. Second, set-up the DHCP and TFTPservices/daemons on server/router/PC to netboot with openwrt-mikrotik-initramfs-kernel.bin.
How do I do that, in layman’s terms? What are the step-by-step instructions? Please help me out on this. I would would really appreciate that.

May 8, 2020, 2:04 PM by

Take a look at step 3 of the long read section of the wiki which explains how to export the license key.

Set up the TFTP server as explained in the previous link and download the initramfs to TFTP's directory.
Then it's just a matter of forcing netboot on the device and it will pull the image and boot it.

Word of advise: this is not an easy task, and although all steps are safe in nature, it is still possible to brick the device thus requiring other types of access to the device.

Said that, let me know if you still need a more detailed description and I'll be happy to help.

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MikroTiks cannot be bricked easily...unless you somehow try to change the bootloader outside of a manner provided by the OEM (which I think would require removing the chip from the board).

But yes, serial access may be required (e.g. to enable TFTP client).