# facebookincubator/katran

A high performance layer 4 load balancer

Repository: https://github.com/facebookincubator/katran
Canonical: https://ross.abutalabs.com/products/katran
Language: C
License: GPL-2.0
License Family: copyleft
Last push: 2026-08-26T16:36:28+00:00

## Health v2 (maintenance only)
Score: 77/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 35, longevity 100
- inputs: {"age_days": 3050, "days_push": 7, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 5304, forks 548 (observed 2026-08-28T04:09:15.348484+00:00)

## What it is
Katran is a C++ library and BPF program for building a high-performance layer 4 load balancing forwarding plane. It leverages the Linux kernel's XDP infrastructure for fast in-kernel packet processing.

## Use cases
- build a high-performance layer 4 load balancer
- scale out layer 7 load balancers with an L4 forwarding plane
- process packets in-kernel with XDP for maximum throughput
- replace DNS or anycast-based traffic distribution with an L4 LB
- distribute traffic across backend servers at line rate

## When to choose
- you need blazing-fast L4 load balancing that scales linearly with NIC RX queues
- you run a recent Linux kernel and can deploy XDP/eBPF-based networking
- you want a programmable forwarding plane with gRPC or Thrift control endpoints

## When to avoid
- you need a layer 7 load balancer that terminates TCP/TLS sessions
- you need a solution that runs on non-Linux platforms or older kernels
- you want a turnkey appliance rather than a library to integrate

## Facets
- artifact type: library
- maturity: active
- function: networking, proxy, load-testing
- domain: networking, microservices, performance, infrastructure-as-code
- platform: cpp, c
- tags: load-balancer, xdp, ebpf, layer4, forwarding-plane, bpf, linux

## Member repositories
- facebookincubator/katran (main) score 77

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:15.348484+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:59:00.504288+00:00, confidence not recorded.
  - readme: https://github.com/facebookincubator/katran (fetched 2026-08-28T04:09:15.348484+00:00, sha ac821cca6861)
- Data as of 2026-08-30T08:39:29.467469+00:00.