enable automatic ssh login on truenas server
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# Download and install puTTY
https://www.chiark.greenend.org.uk/~sgtatham/putty/latest.html

# Run PuTTYgen
# If you have a .ppk file already, load your public key from the previously saved .ppk file (folder is usually C:\Users\%USERNAME%\.ssh\)
# Otherwise generate a private/public key pair using the PuTTYgen tool as follow:
#   - Select radio button RSA, entering 4096 number of bits or ECDSA, entering nistp384 or nistp521
#   - Click on Generate and move mouse cursor randomly over the blank area
#   - Enter Key passphrase and confirmation (remember this passphrase as you will enter this for all future Windows sessions)
#   - Click on Save private key (save in folder C:\Users\%USERNAME%\.ssh\)

# Open truenas ssh session as the user for who you want to enable auto login
# Navigate to home folder:
cd ~
# check if .ssh folder exists, if not, create folder:
mkdir ~/.ssh
# Select and copy text in PuTTYgen window under heading "Public key for pasting in to OpenSSH authorized_keys file" to clipboard
# In the truenas shell, use the copied text in the following command:
echo 'public-key-copied-from-PuTTYgen-window' >> ~/.ssh/authorized_keys
# test by opening new / another truenas ssh session, which should open truenas shell without login request