How do I resolve the "org.elasticsearch.indices.IndexClosedException" Events Service error?

[Deepanshu.Grover]

Problem 

Sometimes the post-upgrade Events Service can fail with this error:

"org.elasticsearch.indices.IndexClosedException: closed". 

The cause for this can be the indexes that are left closed, which will look like this:

close default_c55c0f7e-fb9e-429a-a6a7-6732dbeb6b21___biz_txn_v1___2018-03-16_19-05-00

close default_c55c0f7e-fb9e-429a-a6a7-6732dbeb6b21___dbmon-wait-time___2018-03-21_05-05-01

close xxxxx_7626f743-d1da-4714-a186-de55193c73a9___dbmon-query-stat___2018-03-21_05-05-01

Solution 

To open these indexes, manually run the following command for changing the close status to open status from Events Service host:

curl -XPOST 'localhost:9200/<my_index>/_open'

For three(n) indexes, run the command three(n) times to resolve the issue.