我们怎样才能在aws elasticache redis-cluster中看到哪些节点是主节点还是副本节点？

Question

在以下链接：

http://docs.aws.amazon.com/AmazonElastiCache/latest/UserGuide/ClientConfig.ReplicationGroup.html

以下内容：

REPLICATIONGROUP  my-repgroup  My replication group  available

  CLUSTERID  my-redis-primary
  CLUSTERID  my-replica-1
  NODEGROUP  0001  my-repgroup.f310xz.ng.0001.cache.amazonaws.com  6379  available
        NODEGROUPMEMBER  my-redis-primary    0001  my-redis-primary.f310xz.0001.cache.amazonaws.com   6379  us-west-2a  primary
        NODEGROUPMEMBER  my-replica-1        0001  my-replica-1.f310xz.0001.cache.amazonaws.com       6379  us-west-2b  replica
Connecting to Clusters in a Replication Group (ElastiCache API)

在上面，向极右 有'主要'和'复制'

截至今天，在aws控制台中， 当我给'describe-replication-groups'命令时 我没有看到'主要'和'复制'

相反，我看到如下所示：

"NodeGroupMembers": [
    {
        "PreferredAvailabilityZone": "us-west-2b", 
        "CacheNodeId": "0001", 
        "CacheClusterId": "ec-redis-cluster1-0001-001"
    }, 
    {
        "PreferredAvailabilityZone": "us-west-2b", 
        "CacheNodeId": "0001", 
        "CacheClusterId": "ec-redis-cluster1-0001-002"
    }, 
    {
        "PreferredAvailabilityZone": "us-west-2b", 
        "CacheNodeId": "0001", 
        "CacheClusterId": "ec-redis-cluster1-0001-003"
    }
]

我尝试了各种命令，找不到。

以什么方式，我能看到一些分片/节点是主/副本的细节

提前致谢

Answer 1

echo "cluster nodes" | redis-cli -c -h redis-cluster | grep master

Answer 2

创建为多节点设置时，AWS Elasticache Redis设置有2种模式 - 启用和禁用群集模式，如here所述。这对手头的问题很重要。

如果您的Elasticache集群处于集群模式，则禁用

aws describe-elasticache-replication-groups --replication-group-id test-1 

将显示类似于此的输出：

{
  "CurrentRole": "replica",
    "PreferredAvailabilityZone": "us-west-1c",
    "CacheNodeId": "0001",
    "ReadEndpoint": {
      "Port": 6379,
      "Address": "xxxx"
    },
    "CacheClusterId": "xxxx"
},
{
  "CurrentRole": "primary",
  "PreferredAvailabilityZone": "us-west-1c",
  "CacheNodeId": "0001",
  "ReadEndpoint": {
    "Port": 6379,
    "Address": "xxxx"
  },
  "CacheClusterId": "xxxx"
}

它可以帮助您确定目标节点的主要角色或副本角色。在启用AWS Elasticache集群模式时，关键的CurrentRole不可用

aws describe-elasticache-replication-groups --replication-group-id test-2 

将显示类似于的输出：

{
    "PreferredAvailabilityZone": "us-west-1c",
        "CacheNodeId": "0001",
        "CacheClusterId": "xxxxx"
},
{
    "PreferredAvailabilityZone": "us-west-1c",
    "CacheNodeId": "0001",
    "CacheClusterId": "xxxxxxx"
},

上面的输出没有CurrentRole或任何其他相应的键，可以深入了解节点的角色。在这种情况下，您有2个选项：

1. 如果您可以访问AWS Elasticache Redis群集的端口6379 - 请按照Abhishek的上一个答案获取主​​/从信息。
2. 如果您无权访问群集，即如果您正在编写AWS Lambda或某些代码未在无法访问群集的端口6379的计算机上运行，​​则迂回方式是检查每个群集的IsMaster指标每个分片的节点： aws cloudwatch get-metric-data --cli-input-json file://test.json

test.json看起来像这样：

{
  "MetricDataQueries": [
    {
      "Id": "is_master_test",
      "MetricStat": {
        "Metric": {
          "Namespace": "AWS/ElastiCache",
          "MetricName": "IsMaster",
          "Dimensions": [
            {
              "Name": "CacheClusterId",
              "Value": "xxxxx"
            },
             {
              "Name": "CacheNodeId",
              "Value": "0001"
            }
          ]
        },
        "Period": 60,
        "Stat": "Minimum",
        "Unit": "Count"
      },
      "Label": "is_master_test",
      "ReturnData": true
    }
  ],
  "StartTime": "2019-06-12T10:08:0000",
  "EndTime": "2019-06-12T10:09:0000"
}

如果目标节点是主节点，则输出将如下所示：

{
    "MetricDataResults": [
        {
            "Timestamps": [
              "2019-06-12T10:05:00Z"
            ],
            "StatusCode": "Complete",
            "Values": [
              1.0
            ],
            "Id": "is_master_test",
            "Label": "is_master_test"
        }
    ]
}

如果目标节点不是主节点，则输出将如下所示：

{
    "MetricDataResults": [
        {
            "Timestamps": [
                "2019-06-12T10:05:00Z"
            ],
            "StatusCode": "Complete",
            "Values": [
                0.0
            ],
            "Id": "is_master_test",
            "Label": "is_master_test"
        }
    ]
}

请注意，我使用度量“最小值”来检查此节点是否至少在最后1分钟内保持为主节点。