You must have an FTP or z/OSMF connection to use the views in the z/OS perspective.
You must have at least one connection credential before you can connect to a system. A credential is a repository for a user ID and password combination. For more information, see Defining connection credentials.
The connection and associated credential are displayed in the Host Connections view.
If the connection is successful, the connection name is displayed in the workbench window next to a green icon.
If the connection is not successful, the connection name is displayed in workbench window next to a red icon. An error message is displayed in the workbench status bar providing a reason for the failure. Check the values in the fields, correct any errors, and try to connect again.