SFTP - PPK formats, key strengths and passphrase lengths

Help & Support
1

I have recently been updating key files and I am having problems because the PPK key format DO uses is not current. I have had to download and use PuTTYgen v0.73 to generate the required PPK files. Unfortunately this does not support some of the newer key strengths.

Second problem, is there a string length/ character restriction on the passphrase? If, for example, I use a passphrase containing 100 characters DO never seems to accept this and keeps popping up asking for the password. Using something like WinSCP works fine.

1 Like
2

Support for newer PuTTY key types is on our list.

Password length looks limited to 80 characters, from a quick look. I'm not sure if that's arbitrary or if there's an underlying reason for it. I think the password will always be hashed, and the hash is a fixed size (for a given algorithm), so beyond a certain length there isn't much to be gained from longer and longer passwords.