Unifi Switch Flex setup and documentation

I really like Unifi's networking gear. I have a Dream Machine Pro, a half dozen of their access points, and just bought my first switch from them, the UniFi Switch Flex 5-Port Managed Gigabit PoE - it's perfect for connecting my access points and security cameras to my main network.

For my use case, I have to mount the switch outside, which meant I had to also buy a weatherproof Unifi Switch Flex Utility box - so far so good.

When the packages arrived I opened the boxes in my office and much to my surprise, although the Switch Flex Utility includes a PoE adapter, it doesn't contain an A/C plug!!
I had to cut apart a power cord I had laying around, strip the insulation off the ends... and wire the PoE adapter myself.
Needless to say this was unexpected, not documented, and a big inconvenience.

I got the box mounted, plugged in my new PoE adapter and all my devices, adopted the new switch through my Dream Machine Pro, and more fun awaited me - my security cameras and access points were endlessly power cycling! So frustrating. I looked for loose or shorted connections but couldn't find anything wrong.

Then I did what any self-respecting nerd would do: I searched the internet for "Unifi Switch Flex power cycling" and discovered the solution: For some inexplicable reason, the Switch Flex has to be manually configured to work in PoE mode! What??!

Here are the steps (I used the web interface):

  1. In your Controller (Dream Machine Pro, Dream Machine, or other) choose the Flex switch (Devices / Flex) and Choose "Settings"
  2. Choose "Services", and expand this section of the menu.
  3. SCROLL DOWN to Power Source, select PoE Injector
  4. Click Apply Changes.

Now your PoE devices will be happy, you'll be happy, and Unifi will owe me a debt of gratitude for documenting this ordeal!

Enjoy.