使用rclone迁移windows服务器的数据盘，现在打算使用SFTP模式，目的端22端口一直不通，是不是要自己搭建一个SFTP服务才可以？源端安装了rclone，然后在配置文件的时候，有一些参数不知道对不对，求指导
host就是目的端的公网IP
user就是windows远程的Administrator
port：22
SSH password, leave blank to use ssh-agent.
Choose an alternative below. Press Enter for the default (n).
y) Yes, type in my own password
g) Generate random password
n) No, leave this optional password blank (default)
这个是选择什么？
Option key_pem.
Raw PEM-encoded private key.
If specified, will override key_file parameter.
Enter a value. Press Enter to leave empty.
这个需要选择吗？
Option key_file.
Path to PEM-encoded private key file.
Leave blank or set key-use-agent to use ssh-agent.
Leading ~ will be expanded in the file name as will environment variables such as ${RCLONE_CONFIG_DIR}.
Enter a value. Press Enter to leave empty.
这个需要选择吗？
Option key_file_pass.
The passphrase to decrypt the PEM-encoded private key file.
Only PEM encrypted key files (old OpenSSH format) are supported. Encrypted keys
in the new OpenSSH format can't be used.
Choose an alternative below. Press Enter for the default (n).
y) Yes, type in my own password
g) Generate random password
n) No, leave this optional password blank (default)
这个怎么选择？