当我尝试通过命令行连接到服务器时：
ssh -vvv acmw@<ip>
并显示：
OpenSSH_7.6p1 Ubuntu-4, OpenSSL 1.0.2n 7 Dec 2017
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug2: resolving "<ip>" port 22
debug2: ssh_connect_direct: needpriv 0
debug1: Connecting to <ip> [<ip>] port <port>.
debug1: connect to address <ip> port <port>: Connection timed out
ssh: connect to host <ip> port <port>: Connection timed out
当我将Ubuntu升级到18.04时会发生这种情况