mac putty ppk 사용

Homebrew 필요.. (패키지 관리자)

> /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

> brew install putty

> puttygen privatekey.ppk -O private-openssh -o privatekey.pem

> ssh -i privatekey.pem {user_id}@{server_ip}