SSH

Generate ssh key / identity

ssh-keygen -t ed25519 -C "[email protected]" -f id_ed25519_serge

SSH-Agent (optional)

List all identities

ssh-add.exe -l

Delete all identities

ssh-add.exe -D

Add a identity

ssh-add.exe   .\id_ed25519_serge

Setup ssh config

Choose ssh identity file for a host

vi ~/.ssh/config

Host github.com
    HostName github.com
    User git
    IdentityFile ~/.ssh/id_ed25519_serge
    IdentitiesOnly yes 

Verify identity

ssh -vT   [email protected]      
...
Hi jdedev! You've successfully authenticated, but GitHub does not provide   shell access.
...

delete known_hosts entry line

delete line # 6

sed -i '6d' ~/.ssh/known_hosts