SFTP-SERVER(8) System Manager's Manual SFTP-SERVER(8)

sftp-server —
SFTP server subsystem

sftp-server [-ehR] [-d start_directory] [-f log_facility] [-l log_level] [-u umask]

sftp-server is a program that speaks the server side of SFTP protocol to stdout and expects client requests from stdin. sftp-server is not intended to be called directly, but from sshd(8) using the Subsystem option.

Command-line flags to sftp-server should be specified in the Subsystem declaration. See sshd_config(5) for more information.

Valid options are:

start_directory
specifies an alternate starting directory for users. The pathname may contain the following tokens that are expanded at runtime: %% is replaced by a literal '%', %h is replaced by the home directory of the user being authenticated, and %u is replaced by the username of that user. The default is to use the user's home directory. This option is useful in conjunction with the sshd_config(5) ChrootDirectory option.
Causes sftp-server to print logging information to stderr instead of syslog for debugging.
log_facility
Specifies the facility code that is used when logging messages from sftp-server. The possible values are: DAEMON, USER, AUTH, LOCAL0, LOCAL1, LOCAL2, LOCAL3, LOCAL4, LOCAL5, LOCAL6, LOCAL7. The default is AUTH.
Displays sftp-server usage information.
log_level
Specifies which messages will be logged by sftp-server. The possible values are: QUIET, FATAL, ERROR, INFO, VERBOSE, DEBUG, DEBUG1, DEBUG2, and DEBUG3. INFO and VERBOSE log transactions that sftp-server performs on behalf of the client. DEBUG and DEBUG1 are equivalent. DEBUG2 and DEBUG3 each specify higher levels of debugging output. The default is ERROR.
Places this instance of sftp-server into a read-only mode. Attempts to open files for writing, as well as other operations that change the state of the filesystem, will be denied.
umask
Sets an explicit umask(2) to be applied to newly-created files and directories, instead of the user's default mask.

For logging to work, sftp-server must be able to access /dev/log. Use of sftp-server in a chroot configuration therefore requires that syslogd(8) establish a logging socket inside the chroot directory.

sftp(1), ssh(1), sshd_config(5), sshd(8)

T. Ylonen and S. Lehtinen, SSH File Transfer Protocol, draft-ietf-secsh-filexfer-02.txt, October 2001, work in progress material.

sftp-server first appeared in OpenBSD 2.8.

Markus Friedl <markus@openbsd.org>
July 16, 2013 BSD