ElasticSearch入门之索引库配置管理(settings), 零停机复制索引库(修改分片数) 10

以你之姓@ 2021-10-13 21:53 627阅读 0赞

# 1. 索引库配置 #

**所谓的settings就是用来修改索引分片和副本数的;**  
比如有的重要索引, 副本数很少甚至没有副本, 那么我们通过setting来添加副本数.

*  新建一个索引库 document

DELETE document
    PUT document
    { 
      "mappings": { 
        "article" : { 
          "properties":
          { 
            "title" : { "type": "text"} , 
            "author" : { "type": "text"} , 
            "titleScore" : { "type": "double"} 
            
          }
        }
      }
    }

*  查看副本数

GET /document/_settings

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjY0MTkwOQ_size_16_color_FFFFFF_t_70]  
**可以看到当前的副本数是1**,

*  那么为了提供容错性, 我们可以把副本数改为2;

PUT /document/_settings
    { 
      "number_of_replicas": 2
    }

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjY0MTkwOQ_size_16_color_FFFFFF_t_70 1]

*  副本数能够修改,分片数无法修改,修改分片数会报错

PUT /document/_settings
    { 
      "number_of_shards": 3
    }

![在这里插入图片描述][20190816111245703.png]

# 2. 零停机复制索引库,通过复制索引库来改变分片数 #

实际生产，对于文档的操作，偶尔会遇到这种问题：  
我们发现,setting设置无法修改分片数,但是如果我们后期数据量增多了, 集群规模大了,就要增加分片数来适应大的集群, 怎么办呢? 前提是es集群不能停机  
**那么我们就复制一个索引库, 对新索引库设置新的配置, 将旧索引库的数据拷贝到新索引库中.**

*  新建一个索引库**articles1**, 并添加数据

DELETE articles1
    PUT articles1
    {   
        "settings":{   
             "number_of_shards":3,  
             "number_of_replicas":1  
        },  
        "mappings":{   
             "article":{   
                 "dynamic":"strict",  
                 "properties":{   
                     "id":{ "type": "text", "store": true},  
                     "title":{ "type": "text","store": true}, 
                     "readCounts":{ "type": "integer","store": true},  
                     "times": { "type": "text", "index": false}
                 }  
             }  
        }  
    }
    
    
    PUT articles1/article/1
    { 
      "id" : "1",
      "title" : "世界1",
      "readCounts" : 2 , 
      "times" : "2018-05-01"
    }
    
    get articles1/article/1

*  新建索引库articles2

DELETE articles2
    PUT articles2
    {   
        "settings":{   
             "number_of_shards":5,  
             "number_of_replicas":1  
        },  
        "mappings":{   
             "article":{   
                 "dynamic":"strict",  
                 "properties":{   
                     "id":{ "type": "text", "store": true},  
                     "title":{ "type": "text","store": true}, 
                     "readCounts":{ "type": "integer","store": true},  
                     "times": { "type": "date", "index": false}
                 }  
             }  
        }  
    }  
    }
    
    
    GET articles2/article/1

*  将articles1的数据拷贝到articles2中

POST _reindex
    { 
      "source": { 
        "index": "articles1"
      },
      "dest": { 
        "index": "articles2"
      }
    }
    
    GET articles2/article/1

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[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MjY0MTkwOQ_size_16_color_FFFFFF_t_70 1]: /images/20211013/1b850566d96e494b8fc2e2845e6e11fd.png
[20190816111245703.png]: /images/20211013/d718d4ba82034dc9bd66994ecfbb6333.png