Internal-sftp

https://linux.die.net/man/8/sftp-server

Subsystem sftp internal-sftp

https://serverfault.com/a/274992

Subsystem   sftp    internal-sftp -f AUTH -l INFO

SFTP file transfers can be logged using LogLevel INFO or VERBOSE

Activities

• Review Sftp configuration
• auth.log

Related terms

• LogLevel

See also

• sftp, sftp chroot configuration, Filezilla, Core FTP, sshfs, internal-sftp, sshd_config, SFTP protocol, Secure file transfer program (sftp)

https://en.wikibooks.org/wiki/OpenSSH/Logging_and_Troubleshooting#Logging_SFTP_File_Transfers