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convert PuTTY .ppk keys to OpenSSH format

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puttygen id_rsa.ppk -O private-openssh -o id_rsa
puttygen id_rsa.ppk -O public-openssh -o id_rsa.pub


mv -i ~/id_rsa* ~/.ssh/ # -i is being used to make sure not overwrite
chmod 400 ~/.ssh/id_rsa
chmod 644 ~/.ssh/id_rsa.pub