Ssh keys manipulation

new way on Debian:

ssh-copy-id -i ~/.ssh/one_key_rsa.pub example.com

Old way

ssh root@bk1 mkdir .ssh && chmod 700 .ssh
scp id_rsa.pub root@bk1:~/.ssh/authorized_keys

ssh root@db mkdir .ssh && chmod 700 .ssh
scp id_rsa.pub root@db:~/.ssh/authorized_keys

cat $HOME/.ssh/id_rsa.pub |ssh -l lz newapp04.hotchalk.com \
    "(mkdir .ssh&>/dev/null;chmod 700 .ssh && cat - >> .ssh/authorized_keys) && chmod 600 .ssh/authorized_keys"

Print fingerprint if key file is valid

ssh-keygen -l -f input_key_file

Generate public key from private key

ssh-keygen -y -f input_key_file >input_key.pub