frp — Fast Reverse Proxy to Expose Local Servers Behind NATs and Firewalls

What it is

frp is a high-performance reverse proxy written in Go that exposes local HTTP, TCP, and UDP services to the public internet through a relay server. It is the self-hosted alternative to ngrok and Cloudflare Tunnel. You run a server component (frps) on a public VPS and a client component (frpc) on your local machine. Traffic routes through the relay.

This tool is for developers who need to expose local development servers, demo applications, or home lab services to the internet without complex networking setups.

How it saves time or tokens

frp eliminates the need for port forwarding, dynamic DNS, or VPN setup. A simple configuration file connects your local service to a public URL in seconds. Unlike ngrok, frp is self-hosted with no subscription limits on connections, bandwidth, or custom domains.

How to use

1. Set up frps on a public server.
2. Configure frpc on your local machine.
3. Start both components.
4. Access your local service via the public server's address.

# On your public server - run frps
./frps -c frps.toml

# On your local machine - run frpc
./frpc -c frpc.toml

Example

Server configuration (frps.toml):

bindPort = 7000
vhostHTTPPort = 80
vhostHTTPSPort = 443

Client configuration (frpc.toml):

serverAddr = 'your-server.com'
serverPort = 7000

[[proxies]]
name = 'web'
type = 'http'
localPort = 3000
customDomains = ['dev.your-server.com']

[[proxies]]
name = 'ssh'
type = 'tcp'
localPort = 22
remotePort = 6000

Now dev.your-server.com routes to your local port 3000, and SSH is accessible on port 6000.

Related on TokRepo

• DevOps tools — Networking and infrastructure tools
• Self-hosted solutions — Self-hosted alternatives

Common pitfalls

• You need a public server (VPS) to run frps. This is an ongoing cost, unlike free-tier ngrok.
• Unencrypted frp traffic can be intercepted. Enable TLS between frpc and frps for security.
• Exposing services to the internet creates security risks. Add authentication and access controls.
• frp does not provide automatic HTTPS certificates. Use a reverse proxy like Nginx with Let's Encrypt in front of frps.
• High traffic through frp adds latency compared to direct connections. The relay server becomes a bottleneck for bandwidth-intensive services.
• Review the official documentation before deploying to production to ensure compatibility with your specific environment and requirements.
• Start with default settings and customize incrementally. Changing too many configuration options at once makes debugging harder.