1 前言

一个问题，一篇文章，一出故事。
基于集群性能的需求，笔者想通过将旧索切换到温暖阶段，设置为只读并将其缩减为单个分片。
本章将完成单个索引的只读操作，至于缩减分片数量笔者将在另外一个章节里面整理归纳。

2 最佳实践

2.1 查看修改前的索引的设置

GET /postfix-2024.11.30/_settings

可见如下显示，

{
  "postfix-2024.11.30": {
    "settings": {
      "index": {
        "routing": {
          "allocation": {
            "include": {
              "_tier_preference": "data_content"
            }
          }
        },
        "number_of_shards": "1",
        "provided_name": "postfix-2024.11.30",
        "creation_date": "1732924802036",
        "number_of_replicas": "0",
        "uuid": "kwP_bvB_RK-UssUjYahIvA",
        "version": {
          "created": "8505000"
        }
      }
    }
  }
}

注：以上“postfix-2024.11.29”为索引的名称

2.2 设置索引为只读

PUT /postfix-2024.11.30/_settings
{
  "index": {
    "blocks": {
      "write": true
    }
  }
}

2.3 查看修改后的索引的设置

{
  "postfix-2024.11.30": {
    "settings": {
      "index": {
        "routing": {
          "allocation": {
            "include": {
              "_tier_preference": "data_content"
            }
          }
        },
        "number_of_shards": "1",
        "blocks": {
          "write": "true"
        },
        "provided_name": "postfix-2024.11.30",
        "creation_date": "1732924802036",
        "number_of_replicas": "0",
        "uuid": "kwP_bvB_RK-UssUjYahIvA",
        "version": {
          "created": "8505000"
        }
      }
    }
  }
}

可见如下显示，其中'”write”: “true”‘表示只读，不现实为默认值'”write”: “false”‘

参阅文档
===================

如何熟悉Elasticsearch的索引生命周期管理？