我在使用Vagrant和Docker时遇到了问题，主要是由于共享文件夹的rsync出现了问题。
WDFM32388067A:vagranttest d022051$ vagrant up
Bringing machine 'default' up with 'docker' provider...
==> default: Docker host is required. One will be created if necessary...
default: Vagrant will now create or start a local VM to act as the Docker
default: host. You'll see the output of the `vagrant up` for this VM below.
default:
default: Importing base box 'hashicorp/boot2docker'...
default: Matching MAC address for NAT networking...
default: Checking if box 'hashicorp/boot2docker' is up to date...
default: Setting the name of the VM: docker-host_default_1438155600426_39792
default: Clearing any previously set network interfaces...
default: Preparing network interfaces based on configuration...
default: Adapter 1: nat
default: Forwarding ports...
default: 2375 => 2375 (adapter 1)
default: 22 => 2222 (adapter 1)
default: Running 'pre-boot' VM customizations...
default: Booting VM...
default: Waiting for machine to boot. This may take a few minutes...
default: SSH address: 127.0.0.1:2222
default: SSH username: docker
default: SSH auth method: password
default: Warning: Connection timeout. Retrying...
default: Machine booted and ready!
==> default: Syncing folders to the host VM...
default: Installing rsync to the VM...
The following SSH command responded with a non-zero exit status.
Vagrant assumes that this means the command failed!
rsync --help
Stdout from the command:
Stderr from the command:
sh: rsync: not found
default: The previous process exited with exit code 1.
default: The previous process exited with exit code 1.
从错误信息中不能清楚地看出是ssh还是rsync出了问题。可能是因为ssh超时了。我尝试了所有可能的ssh选项，但什么都没有起作用。例如，我设置了config.ssh.private_key_path，但错误信息仍然完全相同。有人遇到过类似的问题吗？