The USW Flex Mini is Ubiquiti's most cost effective switch, with 5 Gigabit Ethernet ports, with the first one supporting PoE In at 802.3af. It can also be powered by USB C. A power adaptor is included in the box.
Adding to Cloud Hosted UniFi Controller
Getting the USW Flex Mini adopted to HostiFi or any other cloud hosted UniFi Controller requires a few more steps due to it not supporting SSH. There are two ways we can do this.
DHCP Option 43
Local controller L2 discovery method (Recommended)
One of the easiest ways to get the Flex Mini adopted to a remote controller is to spin up a local instance of the UniFi Controller, on your Mac or PC. From there we can adopt it, then migrate it into our HostiFi or cloud hosted UniFi Controller.
First, make sure the switch is connected to Network and powered.
Go to settings >> controller >> enable Make controller discoverable on L2 network and save the changes.
Go to the devices, tab Flex mini should discover as Pending adoption.
After adopting into local UniFi controller you can migrate a site to HostiFi and move the devices to specific sites for a site migration you can follow this guide https://support.hostifi.com/en/articles/3440680-migrate-your-unifi-servers-to-hostifi-with-the-import-export-wizard
After migrating a site to HostiFi you can move it click on switch >> go to config >> manage device >> under forget device there is an option to move the devices, It will be connected to your site.
DHCP option 43 :
Once you powered the switch and connected to the LAN network, you will have to enable DHCP option 43 on your Router LAN network.
Follow this guide to enable DHCP option 43 https://help.ui.com/hc/en-us/articles/204909754-UniFi-Layer-3-Adoption-for-Remote-UniFi-Network-Applications#7
You can enable DHCP option 43 on third party routers such as Pfsense, Mikrotik, Palo Alto etc following the above guide mentioned.
If you have USG as your router Go to settings >> Network >> Edit LAN network >> DHCP UniFi Controller put the controller IP address and save the changes.
Once you applied the changes go to the Devices tab and UniFi Flex Mini will show as Pending adoption.
You can adopt it from the controller by clicking to switch and Hit Adopt.