我在终端中输入了以下命令：
ssh -L 8080:localhost:8888 bb@example
但是，出现以下错误：
ssh: connect to host example port 22: Connection refused
我也尝试过：
sudo apt list --installed | grep openssh-server
但出现以下错误：
The operation couldn’t be completed. Unable to locate a Java Runtime.
Please visit http://www.java.com for information on installing Java.
当我输入
sudo service ssh status
，这是我收到的错误：
sudo: service: command not found