ssh-keygen -t rsa -b 4096 -f rs256.rsa
openssl rsa -in rs256.rsa -pubout -outform PEM -out rs256.rsa.pub
cat rs256.rsa
cat rs256.rsa.pub
ssh-keygen -t rsa -b 4096 -m PEM -f rs256.rsa
openssl rsa -in rs256.rsa -pubout -outform PEM -out rs256.rsa.pub
cat rs256.rsa
cat rs256.rsa.pub