The subject states the question.... is there a limit on how many sub search I can use within a single query.
While doing queries, as an example:
index="MyIndex" source="MySource" computerName=*
| append [ search index="MyOtherIndex" source="MyOtherSource" computerName=*
| table computerName
Everything works as expected up to here
If I add another | append, the search just keeps on parsing search. No results, no errors.
The time preset does not seem to be an issue, I have used from 5 minutes up to 30 minutes where I can confirm there is a result for queries individually.
Additionally, by default subsearches return a maximum of 10,000 results and have a maximum runtime of 60 seconds. In large production environments it is quite possible that the subsearch in this example will timeout before it completes.