During desired nodes updates the system validates that the provided node settings are valid in order to avoid boot looping issues. If one of the node settings depends on a secure setting, the validation fails even when the secure setting is present and correct.
server/src/main/java/org/elasticsearch/node/Node.java
} else {
            throw new IllegalArgumentException("Unknown circuit breaker type [" + type + "]");
        }
    }
    /**
     * Creates a new {@link BigArrays} instance used for this node.
     * This method can be overwritten by subclasses to change their {@link BigArrays} implementation for instance for testing
     */
    BigArrays createBigArrays(PageCacheRecycler pageCacheRecycler, CircuitBreakerService circuitBreakerService) {
        return new BigArrays(pageCacheRecycler, circuitBreakerService, CircuitBreaker.REQUEST);
    }
    /**
     * Creates a new {@link BigArrays} instance used for this node.
     * This method can be overwritten by subclasses to change their {@link BigArrays} implementation for instance for testing
     */
    PageCacheRecycler createPageCacheRecycler(Settings settings) {
        return new PageCacheRecycler(settings);
    }
    /**
     * Creates a new SearchService. This method can be overwritten by tests to inject mock implementations.
     */
    protected SearchService newSearchService(
        ClusterService clusterService,
        IndicesService indicesService,
        ThreadPool threadPool,
        ScriptService scriptService,
        BigArrays bigArrays,
        FetchPhase fetchPhase,
        ResponseCollectorService responseCollectorService,
        CircuitBreakerService circuitBreakerService,