Hope you are doing well
To set up a root user in aws please follow the steps given below :
1) After connecting through putty as ubuntu user , switch to root user
sudo -i
2) Set root password
passwd root
3) Unlock root account
passwd -u root
4) To get back to original default status
sudo passwd -dl root
I think this will resolve the query
Please let me know if you have any further issue regarding this
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