How to have a sftp user account to backup files

After more than a year using Ubuntu 14.04 perfect server and ISPConfig 3.1.1 I am still having a problem. The unique user that i can connect with Bitvise FTP and SSH Telnet client (as also with the other ftp/ssh software clients) .
I have analized and tried all the suggestions at forums to create an sftp user (as we have many websites under this server).
Tried to create via ISP an ftp user, a shel user, etc but nothing works. Tried to install pureftp-common and etc and also nothing works.
How can i have a sftp user and directory siple working?

 

If the user can connect through SSH he should be able to connect by sFTP. E.g. in FileZilla you just add server name, user name, passwort, port 22 and you can use it.

In ISPC it needs to be a shell user. FTP User can't connect through sFTP as sFTP is an extension to ssh: "In computing, the SSH File Transfer Protocol (also Secure File Transfer Protocol, or SFTP) is a network protocol that provides file access, file transfer, and file management over any reliable data stream. It was designed by the Internet Engineering Task Force (IETF) as an extension of the Secure Shell protocol (SSH) version 2.0 to provide secure file transfer capabilities." https://en.wikipedia.org/wiki/SSH_File_Transfer_Protocol

 

Thai is the problem, can't. I have a shell user with mmmmmmmmmmmmmmMMmmm long user name (m=lowercase, M= Uppercase)
Comments: I am aware that FTP and SFTP are different for SFTP been as fact more secure and reliable.
See below the packages installed regarding ftp:
ii ftp 0.17-28 amd64 classical file transfer client
ii openssh-sftp-server 1:6.6p1-2ubuntu2.6 amd64 secure shell (SSH) sftp server module, for SFTP access from remote machines
rc pure-ftpd-common 1.0.36-1.1ubuntu0.1 all Pure-FTPd FTP server (Common Files)
rc pure-ftpd-mysql 1.0.36-1.1ubuntu0.1 amd64 Secure and efficient FTP server with MySQL user authentication

 

SFTP is not related to FTP at all. So forget abut ftp, pure-ftpd if you talk about sftp.

Can the shell user login at the server?

 

No..only root can..

 

Then you need to create a shell account for another user.

 

Yeah. i already have it for months and does not work

 

I have no idea what you did. If you setup a shell account then that can (usually) access by sFTP.... if that shell user can't login by SSH then that shell user can't use sFTP either (I think)

 

I have just created an account via ISOConfig webgui->sites->shell users.

 

Great. It makes sense. I recommend to include a notice at ftp user creation and shell user creation pages to advise isp administrators to does not use jailed to perfectly work as sftp user.

 

The unique problem is when this account is logged in, root or other admin account can't login in via bitvise ftp navigator and ssh telnet terminal.

 

yes. but i found what is causing it...if a use a ssh/sftp to upload files fail2ban include the ip source to banned list and once i have used the same ip connection to test an appliance that use this sftp user to upload files, my connection is being refused until the automatically unbann happens.