When Elasticsearch rejects a request, it stops the operation and returns an error with a
429 response code. Rejected requests are commonly caused by:
Check rejected tasksedit
To check the number of rejected tasks for each thread pool, use the
cat thread pool API. A high ratio of
completed tasks, particularly in the
write thread pools, means
Elasticsearch regularly rejects requests.
Prevent rejected requestsedit
Fix high CPU and memory usage
Prevent circuit breaker errors
If you regularly trigger circuit breaker errors, see Circuit breaker errors for tips on diagnosing and preventing them.