Upgraded to v7.1.1 and now getting eror "Data might be incomplete because your request timed out"

We have upgraded our log server from v6.3.1 to 7.1.1. Now when I do a search for a specific date range it failed due to the following error "Data might be incomplete because your request timed out"

Has anyone encountered this error and been able to resolve issue?

A search that is provided with a “timeout” setting will try stop processing data when the time is up and return with only partial results.

If you’d rather have an error than partial results you can use the “allow partial results setting” to control this behaviour https://www.elastic.co/guide/en/elasticsearch/reference/6.7/search-request-body.html#_parameters_4
Also this might be a related issue/fix.
(https://github.com/elastic/kibana/issues/27209)

Let us know if this helps,
Thanks
Rashmi