SFTP

SFTP is the Secure (or SSH) File Transfer Protocol.

SFTP runs over SSH v2 and is installed as standard with most modern SSH installations.

Paths are specified as remote:path. If the path does not begin with a / it is relative to the home directory of the user. An empty path remote: refers to the user’s home directory.

Note that some SFTP servers will need the leading / - Synology is a good example of this.

Here is an example of making an SFTP configuration. First run

rclone config

This will guide you through an interactive setup process.

No remotes found - make a new one
n) New remote
s) Set configuration password
q) Quit config
n/s/q> n
name> remote
Type of storage to configure.
Choose a number from below, or type in your own value
 1 / Amazon Drive
   \ "amazon cloud drive"
 2 / Amazon S3 (also Dreamhost, Ceph, Minio)
   \ "s3"
 3 / Backblaze B2
   \ "b2"
 4 / Dropbox
   \ "dropbox"
 5 / Encrypt/Decrypt a remote
   \ "crypt"
 6 / FTP Connection
   \ "ftp"
 7 / Google Cloud Storage (this is not Google Drive)
   \ "google cloud storage"
 8 / Google Drive
   \ "drive"
 9 / Hubic
   \ "hubic"
10 / Local Disk
   \ "local"
11 / Microsoft OneDrive
   \ "onedrive"
12 / Openstack Swift (Rackspace Cloud Files, Memset Memstore, OVH)
   \ "swift"
13 / SSH/SFTP Connection
   \ "sftp"
14 / Yandex Disk
   \ "yandex"
15 / http Connection
   \ "http"
Storage> sftp
SSH host to connect to
Choose a number from below, or type in your own value
 1 / Connect to example.com
   \ "example.com"
host> example.com
SSH username, leave blank for current username, ncw
user> sftpuser
SSH port, leave blank to use default (22)
port> 
SSH password, leave blank to use ssh-agent.
y) Yes type in my own password
g) Generate random password
n) No leave this optional password blank
y/g/n> n
Path to unencrypted PEM-encoded private key file, leave blank to use ssh-agent.
key_file> 
Remote config
--------------------
[remote]
host = example.com
user = sftpuser
port = 
pass = 
key_file = 
--------------------
y) Yes this is OK
e) Edit this remote
d) Delete this remote
y/e/d> y

This remote is called remote and can now be used like this:

See all directories in the home directory

rclone lsd remote:

Make a new directory

rclone mkdir remote:path/to/directory

List the contents of a directory

rclone ls remote:path/to/directory

Sync /home/local/directory to the remote directory, deleting any excess files in the directory.

rclone sync /home/local/directory remote:directory

SSH Authentication

The SFTP remote supports three authentication methods:

  • Password
  • Key file
  • ssh-agent

Key files should be unencrypted PEM-encoded private key files. For instance /home/$USER/.ssh/id_rsa.

If you don’t specify pass or key_file then rclone will attempt to contact an ssh-agent.

If you set the --sftp-ask-password option, rclone will prompt for a password when needed and no password has been configured.

ssh-agent on macOS

Note that there seem to be various problems with using an ssh-agent on macOS due to recent changes in the OS. The most effective work-around seems to be to start an ssh-agent in each session, eg

eval `ssh-agent -s` && ssh-add -A

And then at the end of the session

eval `ssh-agent -k`

These commands can be used in scripts of course.

Specific options

Here are the command line options specific to this remote.

--sftp-ask-password

Ask for the SFTP password if needed when no password has been configured.

--ssh-path-override

Override path used by SSH connection. Allows checksum calculation when SFTP and SSH paths are different. This issue affects among others Synology NAS boxes.

Shared folders can be found in directories representing volumes

rclone sync /home/local/directory remote:/directory --ssh-path-override /volume2/directory

Home directory can be found in a shared folder called homes

rclone sync /home/local/directory remote:/home/directory --ssh-path-override /volume1/homes/USER/directory

Modified time

Modified times are stored on the server to 1 second precision.

Modified times are used in syncing and are fully supported.

Some SFTP servers disable setting/modifying the file modification time after upload (for example, certain configurations of ProFTPd with mod_sftp). If you are using one of these servers, you can set the option set_modtime = false in your RClone backend configuration to disable this behaviour.

Limitations

SFTP supports checksums if the same login has shell access and md5sum or sha1sum as well as echo are in the remote’s PATH. This remote checksumming (file hashing) is recommended and enabled by default. Disabling the checksumming may be required if you are connecting to SFTP servers which are not under your control, and to which the execution of remote commands is prohibited. Set the configuration option disable_hashcheck to true to disable checksumming.

Note that some SFTP servers (eg Synology) the paths are different for SSH and SFTP so the hashes can’t be calculated properly. For them using disable_hashcheck is a good idea.

The only ssh agent supported under Windows is Putty’s pageant.

The Go SSH library disables the use of the aes128-cbc cipher by default, due to security concerns. This can be re-enabled on a per-connection basis by setting the use_insecure_cipher setting in the configuration file to true. Further details on the insecurity of this cipher can be found in this paper.

SFTP isn’t supported under plan9 until this issue is fixed.

Note that since SFTP isn’t HTTP based the following flags don’t work with it: --dump-headers, --dump-bodies, --dump-auth

Note that --timeout isn’t supported (but --contimeout is).

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