流量分割 - Jimmy Song

Envoy 提供强大的流量分割功能，支持多种流量控制策略。

权重路由

基本权重配置

route_config:
  virtual_hosts:
  - name: example_vhost
    domains: ["*"]
    routes:
    - match:
        prefix: "/"
      route:
        weighted_clusters:
          clusters:
          - name: service_v1
            weight: 80
          - name: service_v2
            weight: 20

运行时权重配置

route_config:
  virtual_hosts:
  - name: example_vhost
    domains: ["*"]
    routes:
    - match:
        prefix: "/"
      route:
        weighted_clusters:
          runtime_key_prefix: routing.example_service
          clusters:
          - name: service_v1
            weight: 80
          - name: service_v2
            weight: 20

金丝雀发布

基于权重的金丝雀发布

route_config:
  virtual_hosts:
  - name: example_vhost
    domains: ["*"]
    routes:
    - match:
        prefix: "/"
      route:
        weighted_clusters:
          clusters:
          - name: stable_service
            weight: 90
          - name: canary_service
            weight: 10

基于请求头的金丝雀发布

route_config:
  virtual_hosts:
  - name: example_vhost
    domains: ["*"]
    routes:
    - match:
        prefix: "/"
        headers:
        - name: "x-canary"
          string_match:
            exact: "true"
      route:
        cluster: canary_service
    - match:
        prefix: "/"
      route:
        cluster: stable_service

A/B 测试

基于用户 ID 的 A/B 测试

route_config:
  virtual_hosts:
  - name: example_vhost
    domains: ["*"]
    routes:
    - match:
        prefix: "/"
        headers:
        - name: "x-user-id"
          string_match:
            safe_regex:
              google_re2: {}
              regex: ".*[02468]$"  # 偶数用户 ID
      route:
        cluster: variant_a_service
    - match:
        prefix: "/"
        headers:
        - name: "x-user-id"
          string_match:
            safe_regex:
              google_re2: {}
              regex: ".*[13579]$"  # 奇数用户 ID
      route:
        cluster: variant_b_service
    - match:
        prefix: "/"
      route:
        cluster: default_service

基于百分比的 A/B 测试

route_config:
  virtual_hosts:
  - name: example_vhost
    domains: ["*"]
    routes:
    - match:
        prefix: "/"
        runtime_fraction:
          default_value:
            numerator: 50
            denominator: HUNDRED
          runtime_key: routing.ab_test
      route:
        cluster: variant_a_service
    - match:
        prefix: "/"
      route:
        cluster: variant_b_service

蓝绿部署

基于权重的蓝绿切换

route_config:
  virtual_hosts:
  - name: example_vhost
    domains: ["*"]
    routes:
    - match:
        prefix: "/"
      route:
        weighted_clusters:
          clusters:
          - name: blue_service
            weight: 100
          - name: green_service
            weight: 0

基于路由的蓝绿切换

route_config:
  virtual_hosts:
  - name: example_vhost
    domains: ["*"]
    routes:
    - match:
        prefix: "/blue"
      route:
        cluster: blue_service
        prefix_rewrite: "/"
    - match:
        prefix: "/green"
      route:
        cluster: green_service
        prefix_rewrite: "/"
    - match:
        prefix: "/"
      route:
        cluster: blue_service

流量镜像

请求镜像配置

route_config:
  virtual_hosts:
  - name: example_vhost
    domains: ["*"]
    routes:
    - match:
        prefix: "/"
      route:
        cluster: primary_service
        request_mirror_policies:
        - cluster: mirror_service
          runtime_fraction:
            default_value:
              numerator: 10
              denominator: HUNDRED

多镜像配置

route_config:
  virtual_hosts:
  - name: example_vhost
    domains: ["*"]
    routes:
    - match:
        prefix: "/"
      route:
        cluster: primary_service
        request_mirror_policies:
        - cluster: mirror_service_1
          runtime_fraction:
            default_value:
              numerator: 10
              denominator: HUNDRED
        - cluster: mirror_service_2
          runtime_fraction:
            default_value:
              numerator: 5
              denominator: HUNDRED

基于条件的路由

基于时间的路由

route_config:
  virtual_hosts:
  - name: example_vhost
    domains: ["*"]
    routes:
    - match:
        prefix: "/"
        headers:
        - name: "x-time-window"
          string_match:
            exact: "peak"
      route:
        cluster: high_capacity_service
    - match:
        prefix: "/"
      route:
        cluster: normal_service

基于地理位置的路由

route_config:
  virtual_hosts:
  - name: example_vhost
    domains: ["*"]
    routes:
    - match:
        prefix: "/"
        headers:
        - name: "x-region"
          string_match:
            exact: "us-west"
      route:
        cluster: us_west_service
    - match:
        prefix: "/"
        headers:
        - name: "x-region"
          string_match:
            exact: "us-east"
      route:
        cluster: us_east_service
    - match:
        prefix: "/"
      route:
        cluster: default_service

流量控制策略

渐进式流量切换

route_config:
  virtual_hosts:
  - name: example_vhost
    domains: ["*"]
    routes:
    - match:
        prefix: "/"
        runtime_fraction:
          default_value:
            numerator: 5
            denominator: HUNDRED
          runtime_key: routing.progressive_rollout
      route:
        cluster: new_service
    - match:
        prefix: "/"
      route:
        cluster: old_service

基于性能的路由

route_config:
  virtual_hosts:
  - name: example_vhost
    domains: ["*"]
    routes:
    - match:
        prefix: "/"
        headers:
        - name: "x-performance-tier"
          string_match:
            exact: "high"
      route:
        cluster: premium_service
    - match:
        prefix: "/"
      route:
        cluster: standard_service

最佳实践

1. 流量分割策略

使用权重路由进行渐进式发布
结合请求头进行精确控制
实施流量镜像进行测试
监控分割效果

2. 监控和调试

监控各版本的服务指标
设置告警阈值
记录流量分割日志
定期审查分割策略

3. 安全考虑

确保镜像流量不影响生产
验证新版本的安全性
实施回滚机制
监控异常流量

注意事项

流量分割会影响系统性能
需要确保各版本服务兼容性
配置变更需要谨慎测试
需要监控分割效果

流量分割为 Envoy 提供了强大的流量控制能力，合理使用可以实现复杂的部署策略。

发布于: 2024/06/10 • 最后更新: 2025/07/12 • 编辑页面