first of all, you need to download the iso

http://releases.ubuntu.com/18.04/ubuntu-18.04-live-server-amd64.iso.torrent

https://www.ubuntu.com/download/server

 

then you can install it on your pc, or use some virtualizer like vmware or virtualbox

After installing ubuntu 18 server. In my case, I am using a virtualizer and for my confort, I use SSH client. I use putty:

https://www.putty.org/

after logging, you will have something like this:

Enabling root login

Once the Ubuntu 18 server has been set up, all we need to do is modify /etc/ssh/sshd_config and add the line PermitRootLogin yes underneath the Authentication heading.

sudo nano /etc/ssh/sshd_config

sshd_config:

#Authentication:
#LoginGraceTime 2m
PermitRootLogin yes
#StrictModes yes
#MaxAuthTries 6
#MaxSessions 10

Once that’s done, we just need to restart the ssh server

sudo systemctl restart sshd

Now, we need to make sure the root user has a password, if not, we can set one now.

sudo passwd

Enter the new root password, once that’s done, try logging in as root with SSH, it should work now!

For ubuntu 16, install first the next:
sudo apt-get install openssh-server

To prevent all your clients from timing out you need to edit /etc/ssh/sshd_config which is the server side configuration file add these two options:

ClientAliveInterval 120
ClientAliveCountMax 720

Configure ftp server

install ftp

apt-get install vsftpd

then open the next file:

nano /etc/vsftpd.conf

and put the next options as follows:

anonymous_enable=NO

local_enable=YES

write_enable=YES

local_umask=022

finally we restart the service

sudo service vsftpd restart

then you can use a ftp client to log