https://www.zhihu.com/question/19588115/answer/196359285

https://mp.weixin.qq.com/s?__biz=MjM5MjMxODAzMQ==&mid=2652675347&idx=1&sn=99dca5f8cec1309df10e0688dd94314b&chksm=bd402a338a37a32567854b95c6d964e64399d636ea4e010d4e4420c73afc3ca07f30d1be5694&scene=0#rd

ps -A x |grep sshd |grep -v grep