By default, Ubuntu have two users if you have not created another one: ubuntu and www-data
Webinoly is configured to allow ubuntu user have access to all folders and files as manager, for example you can modify config files in your server, and www-data is allowed to only have access to your sites files and this user should be only used to upload files in your sites folders.
To enable the SFTP access for www-data you need the next command:
sudo webinoly -login-www-data
Normally, you have a PEM credential file and you don't need password. If this is not the case you can use the linux command passwd to assign a password.
And by default, port used by SFTP is 22.
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