Name
sftp-server — SFTP server subsystem
Synopsis
sftp-server [-ehR] [-dstart_directory] [-flog_facility] [-llog_level] [-Pblacklisted_requests] [-pwhitelisted_requests] [-uumask] sftp-server-Qprotocol_feature
Description
![[Note]](images/note.gif) | Note |
|---|---|
| When using Co:Z SFTP, this command is not invoked directly, it is invoked using the shell script sftp-server.sh. |
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.
z/OS specific notes:
Features and options that are different from the base sftp-server command are noted below with [z/OS]
Options
-dstart_directoryspecifies an alternate starting directory for users. The pathname may contain the following tokens that are expanded at runtime: %% is replaced by a literal '%', %d 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.
[z/OS feature] The SFTP_ZOS_INITIAL_DIR environment variable, if set, will override the start_directory set by this option. See Configuring the Co:Z SFTP Server in the Co:Z SFTP - User's Guide.
-eCauses sftp-server to print logging information to stderr instead of syslog for debugging.
-flog_facilitySpecifies 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.
-hDisplays sftp-server usage information.
-llog_levelSpecifies 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.
-Pblacklisted_requestsSpecify a comma-separated list of SFTP protocol requests that are banned by the server. sftp-server will reply to any blacklisted request with a failure. The -Q flag can be used to determine the supported request types. If both a blacklist and a whitelist are specified, then the blacklist is applied before the whitelist.
-pwhitelisted_requestsSpecify a comma-separated list of SFTP protocol requests that are permitted by the server. All request types that are not on the whitelist will be logged and replied to with a failure message.
Care must be taken when using this feature to ensure that requests made implicitly by SFTP clients are permitted.
-Qprotocol_featureQuery protocol features supported by sftp-server. At present the only feature that may be queried is “requests”, which may be used for black or whitelisting (flags -P and -p respectively).
-RPlaces 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.
-uumaskSets an explicit umask(2) to be applied to newly-created files and directories, instead of the user's default mask.
On some systems, sftp-server must be able to access /dev/log for logging to work, and use of sftp-server in a chroot configuration therefore requires that syslogd(8) establish a logging socket inside the chroot directory.