OpenSSH / sshd reads configuration data from /etc/ssh/sshd_config. The file contains keyword-argument pairs, one per line. Lines starting with ‘#’ and empty lines are interpreted as comments. Configures an external subsystem such file transfer daemon (SFTP) done through this file only. Arguments should be a subsystem name and a command to execute upon subsystem request. The command sftp-server implements the “sftp” file transfer subsystem. sftp-server is a program that speaks the server side of SFTP protocol. sftp-server is not intended to be called directly, but from sshd using the Subsystem option.

Disable / Turn off sftp server

Open /etc/ssh/sshd_config file:

# vi /etc/ssh/sshd_config

Find line that read as follows:

Subsystem sftp /usr/lib/openssh/sftp-server

Remove or comment out line by prefixing #:

# Subsystem sftp /usr/lib/openssh/sftp-server

Save and close the file. Restart sshd service:

# /etc/init.d/sshd restart