Maglev

Pins a user’s requests to one backend by hashing a request header through a Maglev lookup table

Category: Practical
Task: Pins a user’s requests to one backend by hashing a request header through a Maglev lookup table

Prerequisites: The product runtime and any backend services referenced by this configuration.

Run it: Use ghcr.io/praxis-proxy/praxis:0.7.2 and follow the first reverse-proxy tutorial to mount and start the configuration.

This configuration comes from the selected release. The example has not been run here; external services are not bundled.

Download the source file.

# Maglev Consistent Hashing
#
# Pins a user's requests to one backend by hashing a request header
# through a Maglev lookup table. Compared to ring-based consistent
# hashing, Maglev gives more even load distribution and reassigns
# only ~1/N of traffic when a backend is added or removed. Falls back
# to the URI path when the header is absent.
#
listeners:
  - name: default
    address: "127.0.0.1:8080"
    filter_chains:
      - main

filter_chains:
  - name: main
    filters:
      - filter: router
        routes:
          - path_prefix: "/"
            cluster: backend

      - filter: load_balancer
        clusters:
          - name: backend
            load_balancer_strategy:
              maglev:
                header: "X-User-Id"   # omit to hash on URI path instead
            endpoints:
              - "127.0.0.1:3001"
              - "127.0.0.1:3002"
              - "127.0.0.1:3003"

insecure_options:
  allow_private_endpoints: true # example proxies to local backends