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
import java.nio.file.StandardCopyOption;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.Set;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.FutureTask;
import java.util.concurrent.TimeUnit;
import java.util.function.BiConsumer;
import java.util.function.Function;
import java.util.function.LongSupplier;
import java.util.function.Supplier;
import java.util.function.UnaryOperator;
import java.util.stream.Collectors;
import java.util.stream.Stream;
import javax.net.ssl.SNIHostName;
import static java.util.stream.Collectors.toList;
import static org.elasticsearch.common.util.CollectionUtils.concatLists;
import static org.elasticsearch.core.Types.forciblyCast;
/**
 * A node represent a node within a cluster ({@code cluster.name}). The {@link #client()} can be used
 * in order to use a {@link Client} to perform actions/operations against the cluster.
 */
public class Node implements Closeable {