我们刚刚在一台服务器上安装了 centos8。同样的（准系统）机器之前运行 centos7 就很好。现在我们有很多连接中断；许多 ssh 连接被中断，但并非全部...例如：
> ssh centos8
> ssh some-other-machine
The authenticity of host 'some-other-machine (1.2.3.4)' can't be established.
RSA key fingerprint is SHA256:POwKbdOx0s5IOxVL9gObdtLEbf7oqDDmdHXF9jaA8uQ.
RSA key fingerprint is MD5:0d:85:b1:fb:e0:cd:00:fb:ba:41:8c:57:ee:0c:7e:2f.
Are you sure you want to continue connecting (yes/no)? Connection to centos8 closed by remote host.
Connection to centos8 closed.
所以我在这台centos8机器上，并尝试连接到另一台机器。ssh要求我确认真实性，但不等回答就中断了整个 ssh 会话，我被踢出了 centos8...
我在systemd日志中发现了这一点：
Oct 08 15:04:36 Kubernetes01 sshd[9039]: Timeout, client not responding from user root 10.1.86.100 port 57514
Oct 08 15:04:36 Kubernetes01 sshd[9022]: pam_unix(sshd:session): session closed for user root
这种情况只是偶尔发生，我还没有成功地找到一种模式。该机器非常强大，并且 CPU、RAM、磁盘空间的负载肯定不高......