gRPC 支持

Istio 为 gRPC 协议提供优化的路由和负载均衡。

概述

Istio gRPC 支持：

• 基于 HTTP/2 的负载均衡
• gRPC 健康检查
• Deadline 和 Retry
• 基于 Metadata 的路由

基本配置

apiVersion: networking.istio.io/v1
kind: VirtualService
metadata:
  name: grpc-service
spec:
  hosts:
  - grpc-service
  http:
  - match:
    - uri:
        prefix: /mypackage.MyService/
    route:
    - destination:
        host: grpc-service
        subset: v2
---
apiVersion: networking.istio.io/v1
kind: DestinationRule
metadata:
  name: grpc-service
spec:
  host: grpc-service
  trafficPolicy:
    loadBalancer:
      simple: LEAST_REQUEST  # Suitable for gRPC
    connectionPool:
      http:
        h2UpgradePolicy: UPGRADE
  subsets:
  - name: v2
    labels:
      version: v2

gRPC 健康检查

apiVersion: networking.istio.io/v1
kind: DestinationRule
metadata:
  name: grpc-health-check
spec:
  host: grpc-service
  trafficPolicy:
    outlierDetection:
      consecutiveGatewayErrors: 5
      interval: 30s
      baseEjectionTime: 30s

Retry 配置

apiVersion: networking.istio.io/v1
kind: VirtualService
metadata:
  name: grpc-retry
spec:
  hosts:
  - grpc-service
  http:
  - route:
    - destination:
        host: grpc-service
    retries:
      attempts: 3
      perTryTimeout: 2s
      retryOn: cancelled,deadline-exceeded,resource-exhausted,unavailable

参考资料

• Istio gRPC
• gRPC Load Balancing