es 集群 number_of_shards、number_of_replicas

太过爱你忘了你带给我的痛 2023-02-09 14:18 22阅读 0赞

os: centos 7.4.1708  
es: 7.6.2

三节点的es,参考<<[es 集群三节点安装][es]>>

192.168.56.121  n1
    192.168.56.122  n2
    192.168.56.123  n3

**number\_of\_shards** 是指索引要做多少个分片，只能在创建索引时指定，后期无法修改。  
**number\_of\_replicas** 是指每个分片有多少个副本，后期可以动态修改

**primary shard**：主分片，每个文档都存储在一个分片中，当你存储一个文档的时候，系统会首先存储在主分片中，然后会复制到不同的副本中。默认情况下，一个索引有5个主分片。你可以在事先制定分片的数量，当**分片一旦建立，分片的数量则不能修改。**

**replica shard**：副本分片，每一个分片有零个或多个副本。副本主要是主分片的复制，可以 增加高可用性，提高性能。  
默认情况下，一个主分配有一个副本，但副本的数量可以在后面动态的配置增加。  
副本必须部署在不同的节点上，不能部署在和主分片相同的节点上。

# es 集群基本信息 #

# su - es
    $ curl -X GET 'http://192.168.56.121:9200/_cat/nodes?v'
    ip             heap.percent ram.percent cpu load_1m load_5m load_15m node.role master name
    192.168.56.121           14          99   0    0.00    0.02     0.05 dilm      -      node-1
    192.168.56.123           30          99  14    0.67    0.23     0.11 dilm      -      node-3
    192.168.56.122           32          99   0    0.06    0.03     0.05 dilm      *      node-2

$ curl -XGET http://192.168.56.121:9200/_license
    {
      "license" : {
        "status" : "active",
        "uid" : "bfa9bde9-4b68-45a7-92c9-8c5ac7f122f7",
        "type" : "basic",
        "issue_date" : "2020-05-18T11:57:49.475Z",
        "issue_date_in_millis" : 1589803069475,
        "max_nodes" : 1000,
        "issued_to" : "my-cluster",
        "issuer" : "elasticsearch",
        "start_date_in_millis" : -1
      }
    }

$ curl -XGET 'http://192.168.56.123:9200/_cluster/health?pretty'  
    {
      "cluster_name" : "my-cluster",
      "status" : "green",
      "timed_out" : false,
      "number_of_nodes" : 3,
      "number_of_data_nodes" : 3,
      "active_primary_shards" : 0,
      "active_shards" : 0,
      "relocating_shards" : 0,
      "initializing_shards" : 0,
      "unassigned_shards" : 0,
      "delayed_unassigned_shards" : 0,
      "number_of_pending_tasks" : 0,
      "number_of_in_flight_fetch" : 0,
      "task_max_waiting_in_queue_millis" : 0,
      "active_shards_percent_as_number" : 100.0
    }

# number\_of\_shards #

number\_of\_shards 只能在创建 index 指定，后期无法修改

创建 testindex

curl -XPUT 'http://192.168.56.121:9200/testindex' -H 'Content-Type: application/json' -d ' 
    {
        "settings": {
         "number_of_shards": 10,
    	 "number_of_replicas" : 1
        }
    }
    '

查看 testindex 索引

curl -XGET 'http://192.168.56.121:9200/testindex/_settings?pretty'
    {
      "testindex" : {
        "settings" : {
          "index" : {
            "creation_date" : "1589862851550",
            "number_of_shards" : "10",
            "number_of_replicas" : "1",
            "uuid" : "WimYHgHmTQCL0iniMg-Ybw",
            "version" : {
              "created" : "7060299"
            },
            "provided_name" : "testindex"
          }
        }
      }
    }

# number\_of\_replicas #

number\_of\_replicas 可以在线修改

curl -XPUT 'http://192.168.56.121:9200/testindex/_settings' -H 'Content-Type: application/json' -d ' 
    {
        "index" : {
            "number_of_replicas" : 2
        }
    }
    '

也可以修改模板

curl -X PUT "http://192.168.56.121:9200/filebeat*/_settings" -H 'Content-Type: application/json' -d'
    {
        "index" : {
            "number_of_replicas" : 2
        }
    }
    '

或者创建新的模板

curl -X PUT "http://192.168.56.121:9200/_template/template_log" -H 'Content-Type: application/json' -d'
    {
        "index_patterns" : ["filebeat*"],
        "order" : 0,
        "settings" : {
            "number_of_replicas" : 2
        }
    }
    '

# 删除 index #

查看

$ curl -XGET 'http://192.168.56.121:9200/_cat/indices?v'
    
    health status index     uuid                   pri rep docs.count docs.deleted store.size pri.store.size
    green  open   testindex WimYHgHmTQCL0iniMg-Ybw  10   2          0            0      8.2kb          2.7kb

删除测试用的 index

$ curl -XDELETE  http://192.168.56.121:9200/testindex

参考:

[es]: https://ctypyb2002.blog.csdn.net/article/details/106206608