diff --git a/cmd/serve/sftp/sftp.go b/cmd/serve/sftp/sftp.go
index ef7a8f983..b1be36bb1 100644
--- a/cmd/serve/sftp/sftp.go
+++ b/cmd/serve/sftp/sftp.go
@@ -100,6 +100,17 @@ be used with sshd via ~/.ssh/authorized_keys, for example:
 
     restrict,command="rclone serve sftp --stdio ./photos" ssh-rsa ...
 
+On the client you need to set "--transfers 1" when using --stdio.
+Otherwise multiple instances of the rclone server are started by OpenSSH
+which can lead to "corrupted on transfer" errors. This is the case because
+the client chooses indiscriminately which server to send commands to while
+the servers all have different views of the state of the filing system.
+
+The "restrict" in authorized_keys prevents SHA1SUMs and MD5SUMs from beeing
+used. Omitting "restrict" and using --sftp-path-override to enable
+checksumming is possible but less secure and you could use the SFTP server
+provided by OpenSSH in this case.
+
 ` + vfs.Help + proxy.Help,
 	Run: func(command *cobra.Command, args []string) {
 		var f fs.Fs