I will explain how to change your ssh configuration to allow other users (for e.g. filezilla, winscp or sshfs etc.) and optionally to disable password authentication.
Enable ssh and log in to the nas.
If you make a mistake during this process and need to reset ssh to the default settings so you can login, open the webgui and disable and re-enable ssh. Your config settings won’t be affected.
cp /etc/ssh/sshd_config /usr/local/config
edit /usr/local/config/sshd_config with vi or copy it to your computer, edit it, and copy it back.
Add the following:
AuthorizedKeysFile /usr/local/config/authorized_keys PermitRootLogin yes PubkeyAuthentication yes
Change the AllowUsers line to include the other users you want to allow, for example mine is:
AllowUsers sshd rkitover
If you want to disable passwords add the following:
PasswordAuthentication no ChallengeResponseAuthentication no
From your computer copy the authorized_keys file with the keys you want to allow to the nas:
scp ~/.ssh/authorized_keys sshd@nas:/usr/local/config
MAKE SURE ALL KEYS ARE A SINGLE LINE WITH NO SPACES OR THEY WON’T WORK
Now, edit /usr/local/config/config.xml as described here, make sure to do this very VERY CAREFULLY because you can make your device unbootable.
Find the crond section and add another name entry, call it sshd_config, e.g.:
Add it at the bottom with the next sequential id.
At the bottom of the crond section, add the new sshd_config section, like so:
<sshd_config> <item id="1"> <method>3</method> <1>@reboot</1> <run>sleep 120; pkill sshd; /usr/sbin/sshd -E /var/log/sshd.log -f /usr/local/config/sshd_config &</run> </item> </sshd_config>
Now reboot the nas (e.g. with the reboot command) and wait about 5 minutes.
Your new ssh configuration should be active.