Mikrotik RouterBoard RB750GL

Photos of PCB (circa May 2014). Note that there appear to be testpoints for a serial port connection along with 3.3V power. In addition you can see the spot where USB could be, but the connector and power supply apear to de-populated. The back side was very uninteresting.

Flashing howto

Here is a simple guide to flash OpenWrt on your RB750GL from your linux workstation. For more details and alternative method, see Eric Conrad's blog Installing OpenWRT on a RouterBOARD 750GL.

Get these files (available here for the RC3 Barrier Breaker release):

openwrt-ar71xx-mikrotik-vmlinux-initramfs.elf
openwrt-ar71xx-mikrotik-vmlinux-lzma.elf
openwrt-ar71xx-mikrotik-DefaultNoWifi-rootfs.tar.gz

Rename the file openwrt-ar71xx-mikrotik-DefaultNoWifi-rootfs.tar.gz as openwrt-ar71xx-mikrotik-rootfs.tar.gz.

Set a static ip for your wired interface:

$ sudo ip a a 192.168.0.200/24 dev eth0

Start Dnsmasq (DHCP+TFTP server):

$ sudo dnsmasq --no-daemon --port=0 --dhcp-range="192.168.0.50,192.168.0.150,12h" --enable-tftp --bootp-dynamic --dhcp-boot="openwrt-ar71xx-mikrotik-vmlinux-initramfs.elf" --tftp-root="/path/to/downloaded/files"

Connect the first port of the device to your wired interface, press the RES button on the device and connect it to power. Wait until you see Dnsmasq assigning an ip to the device, then release the button.

Dnsmasq loads the boot image via tftp. Wait until your device reboots (you will see Dnsmasq assigning it an ip again).

Connect to the second ethernet port and assign an ip to your interface from the 192.168.1.0/24:

$ sudo ip a a 192.168.1.200/24 dev eth0

Set up an http server serving the directory where you have the OpenWrt image files:

$ cd /path/to/downloaded/files
$ python -m http.server 8080

Telnet in your router and install OpenWrt to nand:

:!: This step will permanently erase your RouterOS installation. Please backup your RouterOS license if needed.

$ telnet 192.168.1.1
$ wget2nand http://192.168.1.200:8080
$ reboot && exit

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toh/mikrotik/rb750gl.txt · Last modified: 2014/08/25 17:56 by leonaard