Hello,

i got my brand new L009 Router and I wanted to attach it to my network switch (Ubiquiti ES-48-750W). The Idea is, to power the L009 with PoE over the PoE in Port. The L009 should be connected at the same time to the same Switch to an SFP-Port via a DAC Cable.
The Issue is, when the DAC is connected, the L009 can't be powered up with PoE. I have to disconnect the DAC on one side, let the L009 start initally and then I can reconnect the DAC-Cable. After that procedure everything works as expected. But why the L009 doesn't start with connected DAC-Cable?
When I use the power supply, the L009 starts even when both cables, so the DAC and the Cat, are connected.

Thanks for any help.

Lukas

Hi,

Im sorry to say it to you but L009 is not router but switch. L009 do not have good procesor. Better to buy AX2 or AX3 as router.

Well, MikroTik thinks it's a router.

I find your response pointlessly dismissive. The ax² and ax³ won't take the DAC cable the OP requires, and the OP never said anything about gigabit-class routing speeds. The CPU speed limitations of the L009 may not matter for his application. Twice "good enough" is still "good enough".

As to the OP's question, I can only speculate, since I don't have any of these devices.

It's possible it's trying to do what the OP wants but failing due to lack of surge current capacity over PoE.

Another possibility is to try and find a Ubiquiti equivalent to RouterOS's forced-on mode; but beware, this is potentially dangerous as it disables the normal PoE negotiation to find out if the receiving device wants 48V shoved up its clacker.

Thanks for your answers.

The L009 is currently planned as backup router, so no heavy duty requirements, only to have Internet Access when everything else is down. So performance doesn't really matter. But yeah, for me it would be enough with two Ports as the CPU doesn't even have the possibility to handle more. And just to be clear, it is the L009UiGS-RM without WiFi.

I already head a thought, that there is a grounding problem. So one way would be, to maybe try a fiber connection instead of a DAC-Cable.

Any other thoughts or hints?

I am using multimode 10G and 1G as well with MT equipment with different cheap or old transceivers. It works perfectly with most SFPs. That would eliminate any potential difference (grunding) issues. Though I would try the newest stable or beta ROS or another DAC cable. Don´t forget to update RouterBoot as well. https://help.mikrotik.com/docs/display/ ... 0using%20a

BTW: why don´t you just connect 2x Cu 1G ? If you want to power the L009 from the switch, you already have an issue with direct Cu connections between the both, so making the second connection over fiber probably does not matter much. Nothing to gain there, you just add complexity.