UncategorizedExecutionException [执行失败];嵌套：IOException [连接关闭]-ElasticSearch

Question

我正在使用Java客户端（从5.5到7.8）运行重新索引

ReindexRequestBuilder reIndexRequest = new ReindexRequestBuilder(client, ReindexAction.INSTANCE);

        // Basic configuration
        reIndexRequest.source(indexObject.getSourceIndex());
        reIndexRequest.destination(indexObject.getDestinationIndex());

if (reIndex.getMaxretry() != 0) {
            reIndexRequest.setMaxRetries(reIndex.getMaxretry());
        }
        // OpType
        if (!CommonUtils.isEmpty(reIndex.getOptype())) {
            reIndexRequest.request().setDestOpType(reIndex.getOptype());
        }
        // Script
        if (!CommonUtils.isEmpty(reIndex.getScript())) {
            reIndexRequest.script(new Script(reIndex.getScript()));
        }
        // Conflicts
        reIndexRequest.abortOnVersionConflict(false);
        if (reIndex.isAbortonconflict()) {
            reIndexRequest.abortOnVersionConflict(reIndex.isAbortonconflict());
        }
        // Batch Size
        if (reIndex.getBatchsize() != 0) {
            reIndexRequest.request().setSourceBatchSize(reIndex.getBatchsize());
        }
        // Setting Refresh
        if (reIndex.isRefresh()) {
            reIndexRequest.refresh(reIndex.isRefresh());
        }
        // Method to set the max docs
        if (!(reIndex.getMaxdocs() <= 0)) {
            reIndexRequest.maxDocs(reIndex.getMaxdocs());
        }
        // Scroll
        if (reIndex.getScroll() != 0) {
            reIndexRequest.request().setScroll(TimeValue.timeValueMinutes(reIndex.getScroll()));
        }
        // Slice
        if (reIndex.getSlice() != 0) {
            reIndexRequest.setSlices(reIndex.getSlice());
        }

其中切片-1，滚动-10并且批处理大小为100

我收到以下错误消息，

 UncategorizedExecutionException[Failed execution]; nested: IOException[Connection is closed]

让我知道，如果我需要调整任何特定内容以避免此异常。

谢谢， 哈里