How to reinstall RouterOS?

I have a RB2011UiAS-2HnD-IN which has been running OpenWrt for a while. I now want to go back to RouterOS (to pass it on to someone else).

Can anyone tell me how to set about doing this? I probably need to download RouterOS as I don’t think I saved the version that was originally installed. Also do I need any sort of software key?

I have a serial connection available to the RB2011, that was how I was loading OpenWrt. Presumably I can use this to load RouterOS.

Openwrt guide usually describes the way how to revert back to original software. Follow that. Or try the netinstall.

Have you exported device’s license ?

Quote from https://wiki.openwrt.org/toh/mikrotik/rb411
"Are you ready to lose your Mikrotik RouterOS licence? If not, export it from Winbox→System→Licence. "

To be quite honest it’s so long ago that I don’t remember if I exported the licence. If I did what’s likely to be the filename?

I did look at the OpenWrt guide for the Mikrotiks but it says little or nothing about re-installing except to remember to keep the key. Netinstall is WIndows and I don’t have any Windows machines, not any experience of using them.

I’m afraid Netinstall might be the only mean to (re)install RouterOS on a device that does not have a functional RouterOS installed already. If I remember correctly, Netinstall has been reported to work fine under Wine, so that may be an option for you.

Windows + Netinstall. You could virtualize Windows using for example VirtualBox (and bridge network connection). Ask Google how to get Win10 iso, you can do it legally.

Also, you can run Netinstall with Wine running as root with sudo, because of port that is below of 1024.
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