Add New Page: You are not allowed to add pages Select section/namespace. New page title.
 

Ubiquiti NanoStation M - PoE Power Passthrough option

On the Ubiquiti NanoStation M-series devices, it is possible to pass the PoE 24V power signal through the device, from the Main port to the Secondary port. This allows you to use one Ethernet cable from inside of a building to power two rooftop nodes.

Note: Before attempting this, make sure you are using a 24V / 1A PoE power supply. The 24V / 0.5A power supplies that ship with most Ubiquiti routers are not designed to power two units. Check the bottom of the PoE brick for the power specifications if you are unsure.

Advantages:

  • Fewer cables to run, simplified installation.
  • Mesh both devices over Ethernet cable, increasing throughput.

Disadvantages:

  • Single point of failure - one PoE or cable issue can cause two nodes to fail.
  • Meshing over Ethernet still complex to set up.
  • Impossible to TFTP flash the secondary device with a remote reset button (on a PoE), since the secondary device will never see that reset signal.

Given the disadvantage of the higher chance of failure and the complications with TFTP resets, this isn't a recommended procedure. However, in certain cases it might be the only option, so we describe it below.

For the proper wiring, refer to the NanoStation diagram shown here.

  1. Plug in the Ethernet cable coming from your 24V / 1A PoE power supply into the Main port of the first wireless node.
  2. Run a second Ethernet cable from the Secondary port on the first node to the Main port on the second node.
  3. Knock out the plastic tab on the bottom case cover and close up the first node.
  4. Close up the second node.
  5. Power on the first wireless node. The second unit will not power up yet.
  6. Log in to the Administration interface on the first node.
  7. Browse to the Advanced → System → Startup menu.
  8. Scroll to the bottom of this page, and copy the following three commands in to the bottom of the “Local Startup” box, before the text “exit 0”:
echo 8 > /sys/class/gpio/export
echo out > /sys/class/gpio/gpio8/direction
echo 1 > /sys/class/gpio/gpio8/value

Make sure there is the text 'exit 0' at the end of the file, don't put your commands after the line containing that text.

Click “Submit” at the bottom of the page.

Reset the node by browsing to the System → Reboot menu and selecting “Perform reboot”.

About halfway through the first node booting up, the second node will begin to boot. You have now configured the first node with PoE power passthrough.