I’ve just had an interesting problem with an SFTP account that suddenly stopped working from a cron job. When the account was used directly from the bash prompt the response was simply Connection closed immediately.
Every thing was set up correctly as far as
/etc/ssh/sshd_config looked fine but the account wouldn’t connect.
As I don’t have the private key for the user that was connecting to the server, I created a new key pair and added the public key to the
authorized_keys file in the users .ssh folder. Using the following command I got a response that was no more helpful;
psftp firstname.lastname@example.org -i logdrop_pk.ppk
This gave the response;
FATAL: Recieved unexpected end-of-file from SFTP Server
After a couple more checks on the server and no success I decided to try
putty email@example.com -i logdrop_pk.ppk
This opened putty which connected but reported that the password for the user had expired and needed a new one. From here I was able to reset the password then go on the server and set
passwd -x 0 logdrop
to ensure that the aging was deactivated.
So an interesting issue for a Friday afternoon.