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rpxy-l4

rpxy-l4

rpxy-l4 is a sister project of rpxy. While rpxy focuses on Layer 7 HTTP(S) reverse proxying, rpxy-l4 targets Layer 4 proxying for TCP and UDP workloads.

While rpxy-l4 is already working in some real environments, it is an experimental project driven by the author’s research interests. For now, treat this page as an overview and use the upstream repository for detailed setup and operational guidance.

What rpxy-l4 is for

rpxy-l4 is intended for cases where you need to proxy or demultiplex traffic before HTTP exists, or where the traffic is not HTTP at all.

Examples include:

  • TCP and UDP forwarding
  • Protocol multiplexing on the same port
  • SNI and ALPN based forwarding for TLS or QUIC
  • Preserving client IP information with HAProxy PROXY protocol

When to use which project

If you need…Use
HTTP/1.1, HTTP/2, HTTP/3 reverse proxying, TLS termination, ACME, path-based routingrpxy
TCP/UDP proxying, protocol-level demultiplexing, or an L4 proxy in front of rpxyrpxy-l4
HTTP routing plus client IP preservation or L4 traffic steeringrpxy-l4 in front of rpxy

Using rpxy-l4 together with rpxy

One common deployment is:

Client --> rpxy-l4 --> rpxy --> Backend App

In that arrangement, rpxy-l4 handles Layer 4 concerns such as TCP forwarding or PROXY protocol, and rpxy continues to handle HTTP routing, TLS termination, ACME, caching, and other Layer 7 features.

Where to find the full documentation

At the moment, the primary reference for rpxy-l4 is its upstream repository:

For the integration point most relevant to rpxy, see PROXY Protocol.

Documentation