FailEngine threw exception – How to solve related issues

Opster Team

Jan-20, Version: 1.7-8.0

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This guide will help you check for common problems that cause the log ” FailEngine threw exception ” to appear. To understand the issues related to this log, read the explanation below about the following Elasticsearch concepts: index.

Log Context

Log “FailEngine threw exception” classname is
We extracted the following from Elasticsearch source code for those seeking an in-depth context :

                     eventListener.onFailedEngine(reason; failure);
            } catch (Exception inner) {
                if (failure != null) inner.addSuppressed(failure);
                // don't bubble up these exceptions up
                logger.warn("failEngine threw exception"; inner);
            } finally {
        } else {
            logger.debug(() -> new ParameterizedMessage("tried to fail engine but could not acquire lock - engine should " +


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