Doesn't your system refuse root login by ssh by default ? If I remember correctly, on ubuntu server, sshd is configured by default to not allow root login from remote addresses.
On some providers yes, in fact I explicitly enabled root SSH login for those.
Other providers (such as Digital Ocean) use the root account by default even for Ubuntu, although the password is set to a really secure and random one.
Other providers (such as Digital Ocean) use the root account by default even for Ubuntu, although the password is set to a really secure and random one.