Search notes:

~/.ssh/known_hosts

~/.ssh/known_hosts is a user's known hosts file which contains a list of host keys for all hosts the user has logged into that are not already in the systemwide list of known host keys.
The following command gets a listing of the fingerprints along with their random art for all known hosts: 
$ ssh-keygen -lv -f ~/.ssh/known_hosts

known_hosts does not exist

This Stackoverflow answer suggests to use ssh to create ~/.ssh/known_hosts if it does not exist. 
$ ssh-keygen -R 192.168.0.103
Cannot stat /home/rene/.ssh/known_hosts: No such file or directory

$ ssh rene@192.168.0.103
…

See also

ssh-keygen -F
ssh-keygen -H
ssh-keygen -R
man sshd
Known host files

Index

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