Most settings are made once by the installer. Since v0.4.0 the language model is chosen in Settings, not here. harbor config edits the file; harbor start applies it.
Optional. A Tailscale auth key. With it the vault is reachable only on your tailnet, over HTTPS, and nothing listens on the machine's own interfaces. Needed only on first start.
TAILSCALE_HOSTNAME
The name the vault takes in your tailnet.
WEB_ORIGIN
The address the vault is reached at, such as https://harbor.your-tailnet.ts.net.
HARBOR_BIND, HARBOR_WEB_PORT
Without Tailscale, the address and port to publish on: a LAN address, or the address a VPN you run gives the box. Default 127.0.0.1:3000.