尝试将 Redis Sentinel 与 Net Core 2.1 一起使用答案

【问题标题】：Trying to use Redis Sentinel with Net Core 2.1尝试将 Redis Sentinel 与 Net Core 2.1 一起使用
【发布时间】：2020-10-15 01:10:02
【问题描述】：

好吧，我正在使用 Net Core 2.1 和 lib Microsoft.Extensions.Caching.Redis ver 2.1.2，当我只使用一个 Redis 节点时，一切正常。

使用单个节点：

services.AddDistributedRedisCache(ops =>
            {
                ops.Configuration = "localhost:6379";
                ops.InstanceName = "master";
            });

但现在，我正在尝试将 Redis 与 Sentinel 一起使用，因此我将配置更改为（遵循本指南 https://stackexchange.github.io/StackExchange.Redis/Configuration.html）：

 services.AddDistributedRedisCache(ops =>
            {
                ops.Configuration = "localhost,serviceName:mymaster";
                ops.InstanceName = "master";
            });

所以，我有一个 docker-compose.yml 来使用 sentinel 启动 redis 节点：

version: '2'
services:
  redis-master:
    image: bitnami/redis:5.0
    environment:
      ALLOW_EMPTY_PASSWORD: 'yes'
      REDIS_REPLICATION_MODE: 'master'
    ports:
      - '6379:6379'
  redis-slave1:
    image: bitnami/redis:5.0
    environment:
      ALLOW_EMPTY_PASSWORD: 'yes'
      REDIS_REPLICATION_MODE: 'slave'
      REDIS_MASTER_HOST: redis-master
    depends_on:
      - redis-master
    ports:
      - '6380:6380'
  redis-slave2:
    image: bitnami/redis:5.0
    environment:
      ALLOW_EMPTY_PASSWORD: 'yes'
      REDIS_REPLICATION_MODE: 'slave'
      REDIS_MASTER_HOST: redis-master
    depends_on:
      - redis-master
    ports:
      - '6381:6381'
  redis-sentinel:
    image: bitnami/redis-sentinel:5.0
    environment:
      REDIS_MASTER_HOST: redis-master
      REDIS_SENTINEL_DOWN_AFTER_MILLISECONDS: 10000
    ports:
      - '26379:26379'

当我启动我的应用程序时一切正常，所以我关闭了主节点以测试哨兵并在 Asp Net Core 中得到以下错误：

RedisConnectionException: SocketClosed on localhost:6379/Subscription, origin: ProcessReadBytes, input-buffer: 0, outstanding: 0, last-read: 14s ago, last-write: 14s ago, unanswered-write: 1998113s ago, keep-alive: 60s, pending: 0, state: ConnectedEstablished, in: 0, ar: 0, last-heartbeat: 0s ago, last-mbeat: 0s ago, global: 0s ago
Unknown location

RedisConnectionException: No connection is available to service this operation: EVAL; SocketClosed on localhost:6379/Subscription, origin: ProcessReadBytes, input-buffer: 0, outstanding: 0, last-read: 14s ago, last-write: 14s ago, unanswered-write: 1998113s ago, keep-alive: 60s, pending: 0, state: ConnectedEstablished, in: 0, ar: 0, last-heartbeat: 0s ago, last-mbeat: 0s ago, global: 0s ago
StackExchange.Redis.ConnectionMultiplexer.ThrowFailed<T>(TaskCompletionSource<T> source, Exception unthrownException) in ConnectionMultiplexer.cs, line 2000

好吧，如果我再次启动主节点，一切正常，但这不是预期的行为。我希望在关闭主节点后，哨兵将一个从属提升为主，我可以继续使用redis而不会出错。

我错过了什么吗？

【问题讨论】：

标签： asp.net-core .net-core redis stackexchange.redis

【解决方案1】：

很抱歉回复晚了，但我们只是自己解决这个问题。连接 Sentinel 时，需要在连接字符串中指定端口：

services.AddDistributedRedisCache(ops =>
{
    ops.Configuration = "localhost:26379,serviceName:mymaster";
    ops.InstanceName = "master";
});

一旦 ConnectionMultiplexer 连接到 Sentinel 节点，它就会获取主节点并使用它。另外，我发现要完成这项工作需要几个设置：

redisOptions.TieBreaker = "";
redisOptions.AbortOnConnectFail = false;
redisOptions.AllowAdmin = true;

我们还在 .NET Core 3.1 上使用 StackExchange.Redis v2.2.4

【讨论】：