Can we set ignore_malformed flag true of an already existing index in elasticsearch

Question

I'm new to elasticsearch. I'm re-indexing old index to new index. but while re-indexing millions of records sometime, I am getting mapper_parsing_exception exception. so my question is that, Is there a way to set ignore_malformed flag true of an already existing index.

Answer 1

Yes, it's possible to change the ignore_malformed setting dynamically simply by running this:

PUT logstash_june_2019/doc/_mapping
{
  "properties": {
    "createdAt": {
      "type" : "date",
      "ignore_malformed": true             <--- add this
    }
  }
}