USP Server

USP Server is the central component of the UDMG Secure Proxy (USP) platform. It receives inbound connections, applies authentication and session break logic, and routes connections to internal targets. It also exposes SSH tunnels to receive traffic relayed by USP Clients.

Configuration Overview

The USP Server must be explicitly configured with values such as its name, TLS identity, and listener definitions. These must be set before the service can start properly.

• HCL Configuration File: Located at /opt/udmg/etc/usp-server.hcl. This file defines the structured configuration using HCL (HashiCorp Configuration Language), where fields are written using dot notation to express the hierarchy of nested blocks.
• Environment Variable File: Environment variables are loaded from /opt/udmg/etc/usp-server.env via the systemd unit.

info

Any configuration value defined via an environment variable will override the corresponding value in the HCL file.

Configuration File

You can specify the path to the configuration file using one of the following options (in order of precedence):

1. Environment Variable: USP_SERVER_CONFIG
2. Command Line Flag: -c or --config
3. Default File: usp-server.hcl (lowest precedence)

Commands Usage

To view available commands and flags, run:

usp-server -h

To run a command:

usp-server [command]

Available Commands

Command	Description
usp-server [command] --help	Show help for a command
completion	Generate shell autocompletion
help	Display help about commands
start	Start the USP Server

Available Flags

-h, --help      help for usp-server
-v, --version   version for usp-server

Start USP Server

To start the USP Server:

usp-server start [flags]

Flags:

• -c, --config string: Path to the configuration file (default: usp-server.hcl)
• -h, --help: Show help for the start command