1: input hostname, connected prompted username: ubuntu The remote system refused the connection.
Because there is no installation or start using the ssh command su root switch to the root user using the command ps -e |.. Grep ssh to see if the start ssh.
If not return to try using the command sudo apt install openssh-server attempting to install ssh.
As has been installed prompt, use the command ssh /etc/init.d/ssh start to start the service. Try to connect again
// related services /etc/init.d/ssh stop command to stop /etc/init.d/ssh restart to restart the service
2: could not load host key.
The next check is probably because the issue forensic certificates using the command ssh-keygen -A key generation
3: a public key file has not been specified for this session would you like to specify one now
In SecureCRT sessions> properties> Connection> SSH2 uncheck PublicKey.
![](https://upload-images.jianshu.io/upload_images/18451210-c4e0a9ef2ccbc802.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/543/format/webp)
4: Reason: Unable to authenticate using any of the configured authentication methods.
After modifying sshd_config configuration information vim / etc / ssh / sshd_config configuration item PasswordAuthentication value no yes to modify using the ssh command /etc/init.d/ssh restart to restart the service.
Attach vim basic commands.
ESC to exit edit mode:. W Save the file but do not quit vi
:! W forced to save, do not exit vi: wq Save the file and exit vi
:! Wq forced to save the file and exit vi: q does not save the file and exit vi
:! Q Force Quit vi without saving the file
5: The server has disconnected with an error. Server message reads: A protocol error occurred. Change of username or service not allowed: (root,ssh-connection) -> (xxxxxx,ssh-connection)
They are inconsistent with the user name SecureCRT settings and user name entered when logging in SecureCRT sessions> properties> Connection> SSH2 username to modify the agreement.
So far, finally the connection is successful. There are problems in the process of learning to be good at using a search engine. Too many windows10 built ubuntu problem, abandoned in favor of redhat7.6