如何实现等待重试瞬态故障处理策略？

Question

我对 Kafka 和 Polly 还很陌生。我正在寻求有关在将 Admin Client 与 Kakfa Confluent .NET 客户端一起使用时如何实现故障弹性的建议。如果主题在 Blazor Server Web 应用程序启动期间不存在，我将使用 Admin Client 创建主题。

最初，我尝试使用 polly 来实施一个简单的等待和重试策略，如下所列。我期望这会重试可配置次数的创建主题操作。在每次重试尝试之间有一个短暂的可配置等待延迟。如果所有重试尝试都已用尽，则会发出致命错误信号并正常退出应用程序。

等待并重试策略

public static AsyncRetryPolicy BrokerWaitAndRetry(short retryCount, short waitSeconds, ILogger logger)
{
    var pauseBetweenFailures = TimeSpan.FromSeconds(waitSeconds);

    var retryPolicy = Policy
        .Handle<KafkaException>()
        .WaitAndRetryAsync(retryCount, i => pauseBetweenFailures, onRetry: (Exception e, TimeSpan time) =>
        {
            logger.LogInformation($"Retry attempt {time}");
        });
    }
    return retryPolicy;
}

将等待和重试策略与管理客户端实例一起使用来创建主题

var polly = KakaFailurePolicies.BrokerWaitAndRetry(5, 7, _Logger);
await polly.ExecuteAsync(async () =>
{
  await client.CreateTopicsAsync(
    new TopicSpecification[] {
      new TopicSpecification {
        Name = _Config.Topic.Name,
        NumPartitions = _Config.Topic.PartitionCount,
        ReplicationFactor = _Config.Topic.ReplicationCount
      }
    },
    new CreateTopicsOptions
    {
        /** Set low request timeout for basic testing, otherwise would use a higher timeout of 60 seconds*/
        RequestTimeout = TimeSpan.FromSeconds(20)
    }
  );
});

日志和分析

当我尝试运行时，我可以从下面的日志中看到重试一次。但是，不会尝试后续重试。日志突出显示 rdkafka 库检测到并抑制了相同的错误。

我认为这是日志中没有显示后续重试尝试的原因，即底层 rdkafka 库轮询线程正在隐藏后续本地超时错误并继续尝试并连接到经纪人。随后，.NET 客户端无法抛出异常，因为它没有收到失败通知。这意味着 polly 正在等待并运行第二次尝试？

info: Extensions.Hosting.AsyncInitialization.RootInitializer[0]
      Starting async initialization
info: Extensions.Hosting.AsyncInitialization.RootInitializer[0]
      Starting async initialization for WebApp.Kafka.Admin.KafkaAdminService
%3|1609337520.079|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 2ms in state CONNECT)
%3|1609337520.079|ERROR|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: 1/1 brokers are down
%3|1609337520.082|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 2ms in state CONNECT)
info: WebApp.Kafka.Admin.KafkaAdminService[0]
      Admin service trying to create Kafka Topic...
info: WebApp.Kafka.Admin.KafkaAdminService[0]
      Topic::eventbus, ReplicationCount::1, PartitionCount::3
info: WebApp.Kafka.Admin.KafkaAdminService[0]
      Bootstrap Servers::localhost:9092
%3|1609337521.081|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT, 1 identical error(s) suppressed)
%3|1609337521.081|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT, 1 identical error(s) suppressed)
%3|1609337522.083|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 1ms in state CONNECT)
%3|1609337522.083|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 1ms in state CONNECT)
%3|1609337524.089|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337524.089|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337525.090|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337525.090|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337527.097|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337527.097|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337528.096|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337528.096|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337530.106|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337530.106|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337532.115|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337532.115|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337533.119|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337533.119|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337535.128|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337535.128|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337536.128|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337536.128|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337537.129|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337537.129|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337540.133|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337540.133|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
Exception thrown: 'Confluent.Kafka.KafkaException' in System.Private.CoreLib.dll
info: WebApp.Kafka.Admin.KafkaAdminService[0]
      Retry attempt 00:00:07
%3|1609337542.135|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337542.135|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337544.140|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337544.140|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337545.140|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337545.140|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337546.140|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337546.140|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337547.332|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337547.332|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337548.149|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337548.149|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337549.148|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337549.148|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337550.148|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337550.148|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337551.152|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT, 1 identical error(s) suppressed)
%3|1609337551.152|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT, 1 identical error(s) suppressed)
%3|1609337555.171|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337555.171|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337556.171|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337556.171|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337557.177|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337557.177|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337558.176|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337558.176|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337560.180|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337560.180|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337561.183|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337561.183|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337562.186|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337562.186|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337563.186|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337563.186|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337564.191|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337564.191|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337567.200|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337567.200|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337568.204|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337568.204|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337569.208|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337569.208|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337570.212|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 1ms in state CONNECT)
%3|1609337570.212|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 1ms in state CONNECT)
%3|1609337573.222|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337573.222|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337574.225|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337574.226|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337575.230|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337575.230|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337576.229|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337576.229|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337578.234|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337578.234|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337579.238|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337579.238|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337580.241|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337580.241|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337581.245|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT, 1 identical error(s) suppressed)
%3|1609337581.245|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT, 1 identical error(s) suppressed)
%3|1609337583.254|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337583.254|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337584.259|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337584.259|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337585.264|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 1ms in state CONNECT)
%3|1609337585.264|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 1ms in state CONNECT)
%3|1609337586.267|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337586.267|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337587.267|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337587.267|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337588.267|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337588.267|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337589.268|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337589.268|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337591.278|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337591.278|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337592.282|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337592.282|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv6#[::1]:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337593.286|FAIL|rdkafka#producer-1| [thrd:localhost:9092/bootstrap]: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)
%3|1609337593.286|ERROR|rdkafka#producer-1| [thrd:app]: rdkafka#producer-1: localhost:9092/bootstrap: Connect to ipv4#127.0.0.1:9092 failed: Connection refused (after 0ms in state CONNECT)

Confluent Kafka .NET 库在第一次尝试时抛出的错误是 ErrorCode.Local_TimedOut。我认为这对应于 rdkafka:error local timeout?? 经过调查，我发现以下 AdminClient 配置属性与瞬态故障处理相关：

这促使我尝试 Confluent Kafka 的内置瞬态故障处理：

var adminClientBuilder = new AdminClientBuilder(
/** https://github.com/confluentinc/confluent-kafka-dotnet/blob/2b54dd2ab07f6eaa886d88c57143838627b2512f/src/Confluent.Kafka/Config_gen.cs#L826 **/
    new AdminClientConfig()
    {
        BootstrapServers = _Config.Consumer.BootstrapServers,
        Debug = "all",
        SocketTimeoutMs = 20000, // reduced from 60seconds for testing purposes
        SocketMaxFails = 5, // is this synonymous to 5 retries?
    }
 );

在启动过程中稍等片刻后，我就启动了Kafka broker。下面的调试日志显示 rdkafka 线程检测到主代理已启动并且运行ning。但是，未执行创建主题管理操作。

调试日志

由于 space 限制，可在 pastebin 观看。

问题

是否可以配置 rdkafka 以便在尝试将 AdminClient 连接到代理时不会抑制相同的错误？

在上面的例子中，一旦 rdkafka 轮询线程最终检测到代理已启动并且运行ning，为什么 AdminClient 创建主题操作未完成？

如何使用 Confluent Kafka .NET with/without Polly 为 Kafka AdminClient 实施重试和等待失败策略经纪人？

更新

创建一个小型控制台应用程序，可在 pastebin.

获得

如果在每次重试时都创建了一个新的 AdminClient，并且在检测到故障后最终启动了一个代理，那么它将起作用。

但是，如果每次重试都重复使用相同的 AdminClient 实例，并且代理最终在检测到故障后启动，则程序会阻塞。我认为这是因为 rdkafka 库正在抑制客户端的多个本地超时错误。它仅通知 Confluent Kafka .NET 初始故障检测。

有没有更好的方法，而不是在每次重试时都创建一个新的 AdminClient 实例？

Answer 1

在 Confluent Kafka GitHub 存储库中提交 issue 后，这个问题中描述的问题似乎是由于 Confluent Kafka .NET 库中已确认的错误造成的。

库作者 here 提出了解决方法。

基本上，在错误修复之前，每次重试都必须创建一个新的 AdminClient 实例。

如何实现等待重试瞬态故障处理策略？

How To Implement A Wait Retry Transient Fault Handling Policy?

polly

librdkafka

confluent-kafka-dotnet