【ElasticSearch】index read-only

今天在测试环境执行MySQL数据同步到ElasticSearch中时，出现无法写入的问题，并且提示

[FORBIDDEN/12/index read-only / allow delete (api)

排查后发现是ES所在服务器磁盘空间不足，导致索引无法写入，解决方式:

1.扩大磁盘或者删除部分历史索引

2.重置修改只读索引块

在Kibana上修改，如下

某一个索引重置只读模块
PUT /twitter/_settings
{
  "index.blocks.read_only_allow_delete": null
}
所有索引重置只读模块
PUT /_all/_settings
{
  "index.blocks.read_only_allow_delete": null
}

PUT /_cluster/settings
{
  "persistent" : {
    "cluster.blocks.read_only" : false
  }
}

修改默认配置

可以修改为具体的磁盘空间值，也可以修改为百分之多少
临时修改
PUT _cluster/settings
{
  "transient": {
    "cluster.routing.allocation.disk.watermark.low": "100gb",
    "cluster.routing.allocation.disk.watermark.high": "50gb",
    "cluster.routing.allocation.disk.watermark.flood_stage": "10gb",
    "cluster.info.update.interval": "1m"
  }
}
永久修改
PUT _cluster/settings
{
  "persistent": {
    "cluster.routing.allocation.disk.watermark.low": "100gb",
    "cluster.routing.allocation.disk.watermark.high": "50gb",
    "cluster.routing.allocation.disk.watermark.flood_stage": "10gb",
    "cluster.info.update.interval": "1m"
  }
}

参考文档：

https://www.elastic.co/guide/en/elasticsearch/reference/6.8/disk-allocator.html