To permanently change an Ubuntu 20.04 Server’s name edit the /etc/hostname file:
sudo vim /etc/hostname
This will show the current server (host) name:
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Rename Ubuntu 20.04 Server:
Change the name to whatever you want to call the server:
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Save the changes (esc :wq in vim).
You will see that the host still has its old name:
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Reboot the server to update its name to the new name.
Now the server has its new name:
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This change is now permanent.
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