Modify Teleport VPN Subnet on Ubiquiti UniFi Gateway

Current lines of the UniFi Gateway devices, such as the UXG-Fiber that I am using, include a built in VPN server called Teleport. The idea is a simple, zero-configuration VPN solution. When activated, the VPN is configured automatically by selecting an unused subnet from the 192.168.X.0/24 range.

While initial deployment was as simple as advertised, I quickly ran into a problem where UniFi assigned a subnet that overlapped with a subnet on an upstream router. Teleport, being a zero-configuration service, gave no way to actually set what subnet is in use. Insert some curiosity and a solution.

Requirements

  • Administrative access to the UniFi OS Control Plane (Cloud Key or equivalent).
  • SSH access to the UniFi OS Control Plane (Cloud Key or equivalent), required to access the MongoDB.

Summary Steps

  • Gain SSH Access to the UniFi OS Control Plane
  • Determine the Site_ID Value for the Teleport Configuration
  • Modify the Teleport Subnet

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