$ ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/home/john/.ssh/id_rsa): 
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /home/john/.ssh/id_rsa.
Your public key has been saved in /home/john/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:Fc/7cW+u0cIJGgxv7jz+GvZzNfb+NUCNw3m5U+D1s2U john@john-PC
The key's randomart image is:
+---[RSA 2048]----+
|          .   . .|
|           +..+oo|
|        . . o*.=E|
|         =  ..o.*|
|        S = o..+.|
|         o o +.B+|
|          =   BoB|
|         +.o. .=+|
|         .=+oo.o=|
+----[SHA256]-----+


john@john-PC:~/tg-git/devrepo/kms/duan$ cat /home/john/.ssh/
id_rsa       id_rsa.pub   known_hosts  
john@john-PC:~/tg-git/devrepo/kms/duan$ cat /home/john/.ssh/id_rsa.pub 
ssh-rsa AAAB3NzaC1yc2EAAAADAQABAAABAQDndPq+fx6rWBX7cEfUJlnch7dMgvX2oZpJYb1zQA14FCEgOPX7daYVE+Cb+xOGZZD9EJiJZ0CKUn7HDoDC0HU1SqqOTmeUZHJbHvo1+CNmMpQcaaJD5szdygmz7X6dDbN7SdoegLJkNSpfsi0Xu3PkLj//tLyFGh9bTtQcNWAWdPNuJI6zVoacqjZpEJFlRCEUZtVf+y2p2V7aAPjgK05HsMyzPsxWbraM84XyCj6S3t9r+p1irpl5+HzhruHr8B2MtjerhhY/DBpXDR599aRS4RWj935AdMTgpQtJxrBo3U7ETcfsnWgeWW7qlGsHIxobW+wvMuvo9 john@john-PC