https://pdf.yozocloud.cn/index.html#/Pdf2word ：永中PDF工具集 为您提供免费、优质的PDF转换及处理服务
https://www.cnblogs.com/cjsblog/p/9439331.html ：Elasticsearch
https://www.cnblogs.com/cjsblog/p/9459781.html：Logstash
https://www.cnblogs.com/cjsblog/p/9445792.html：Filebeat
https://cloud.tencent.com/developer/article/1451728：单机搭建hadoop+hive+spark环境
https://www.cnblogs.com/mrlinfeng/p/6146866.html: Nginx反向代理，负载均衡，redis session共享，keepalived高可用
https://www.cnblogs.com/mrlinfeng/p/6341225.html: Keepalived+lvs 搭建高可用负载均衡
原文：https://www.cnblogs.com/CGCong/p/11950192.html