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SaKKo
SaKKo

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How I setup my Digital Ocean Ubuntu 20.04 Server?

#beginners #ubuntu

My personal note to setup ubuntu server, my old note is in Quiver.

Before creating a droplet, make sure to select the SSH-KEY that is used login to server.

To generate new key, use this command and input the path you want to store the new key.

ssh-keygen
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After creating a droplet, ssh into server using

ssh -i ~/.ssh/ssh_key root@server_ip
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Create a new user, for example ubuntu

adduser ubuntu
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Make ubuntu a sudoer so that ubuntu can be used instead of root

usermod -aG sudo ubuntu
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Swap user to ubuntu and copy ssh public key to ~/.ssh/authorized_keys

su ubuntu
cd ~
mkdir .ssh
vim authorized_keys  # paste the ssh public key here
exit  # back to root user
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exit again to close this session.

Try login using ubuntu user. If done correctly, there should be no password prompt.

ssh -i ~/.ssh/ssh_key ubuntu@server_ip
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make ubuntu sudo without supplying password

sudo visudo
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Add this line to the last part

ubuntu ALL=(ALL) NOPASSWD:ALL
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ctrl+x y enter to exit the editor

exit to close the session.

SSH back in

ssh -i ~/.ssh/ssh_key ubuntu@server_ip
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run sudo date there should be no password prompt.

Now disable root ssh login

sudo vim /etc/ssh/sshd_config
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Change PermitRootLogin yes to PermitRootLogin no

Add a line AllowUsers ubuntu to allow ubuntu to login.

Then restart ssh.

sudo service ssh restart
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Now exit to close session again and test logging back in to server.

ssh -i ~/.ssh/ssh_key ubuntu@server_ip
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Finally

sudo apt update
sudo apt upgrade
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NOTE: To change SSH Port from 22 to something else

sudo vi /etc/ssh/sshd_config
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Change Port 22 to the port you want.

Restart SSH sudo service ssh restart and then to SSH, use

ssh -i ~/.ssh/ssh_key root@server_ip -p PORT
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Done! Next, try using ansible to setup other softwares.
Also checkout firewall before using in production.

Top comments (2)

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cescquintero profile image
Francisco Quintero 🇨🇴 •

Great article, thanks for sharing!

In a next article you might one to share how to change the default port (22) to something more secure like 34982

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sakko profile image
SaKKo •

Ok, I will add this.

sudo vi /etc/ssh/sshd_config

Change Port 22 to the port you want.

Restart SSH sudo service ssh restart and then to SSH, use

ssh -i ~/.ssh/ssh_key root@server_ip -p PORT