rsync 中 --password-file 选项的语法和先决条件是什么？

没错，

--password-file 仅在连接到 rsync 守护程序时适用。

不过，您可能尚未在守护程序本身中设置它，您设置的密码和您在该调用期间使用的密码必须匹配。
编辑 /etc/rsyncd.secrets，并将该文件的所有者/组设置为具有全局读取权限的 root：root。

#/etc/rsyncd.secrets
root:YourSecretestPassword

要连接到 rsync 守护程序，请使用双冒号后跟模块名称，以及要同步的文件或文件夹（使用 SSH 时不要使用冒号），

RSYNC_PASSWORD="YourSecretestPassword"; rsync -rtv user@remotehost::module/source/ destination/ 

注意：

• 这意味着放弃SSH加密，尽管密码本身不是以纯文本形式通过网络发送的，但您的数据是...
• 这已经是不安全的，永远不会像您的任何用户帐户一样使用相同的密码。
• 为了更好地理解其内部工作原理（如何使特定 IP/进程能够在不需要用户帐户的情况下上传到文件系统的指定区域）：http://transamrit.net/docs/rsync/

rsync -arv -e \
    "sshpass -f '/your/pass.txt' ssh -o StrictHostKeyChecking=no" \
    --progress /your/source id@IP:/your/destination

如果你不安装，也许你必须安装“sshpass”。

尝试了一段时间后，我让它起作用了。由于我从我的实时服务器（和路由器数据）复制到我的笔记本电脑中的本地服务器作为备份用户，密码没有问题未加密，它安全地连接到我家的笔记本电脑上。首先，你需要安装 sshpass if Centos，然后创建一个用户备份并分配一个临时密码。我列出了 -p 选项，以防您的 ssh 端口与默认值不同。yum install sshpass

sshpass -p 'password' rsync -vaurP -e 'ssh -p 2222'  backup@???.your.ip.???:/somedir/public_data/temp/ /your/localdata/temp

Understand SSH RSA is a better permanente alternative and all that, but this is a quick alternative to backup and restore on the go. It works if you are not too concern about security but more concern about your data been backup locally as in an emergency o data recovery. Your user backup password you can change it once the backup is completed. Its a lot faster to setup when your servers change IPs, users, and its in constant modifications (as routers change config and non static IPs, also when routers are not local and you are backing up clients servers locally, where you dont have always access to do SSH. Some of my clients dont even have SSH installed and they dont want to hassle with creating public keys. On some servers only where you have access on a temporary basis. By the way, if you want to do the restore, just reverse the case. Dont need change much, from the same command shell you can do it reversing the order of target and source directories, and creating another backup user with same temp password on the target. After finish, you delete the backup user or change its passwords on target and/or source servers. You can protect even further, as I have done, replacing the password for a one line file using a bash script for multi server environment. Alternative is to use the -f option so the password does not show in the bash history Regards-f "/path/to/passwordfile"

NOTE: If you want to update only modified files then you should use this parameters -h -v -r -P -t as described here https://unix.stackexchange.com/questions/67539/how-to-rsync-only-new-files