Windows 7下Docker Toolbox限制镜像并发下载的方法求助

Got it, let's break this down. The core issue here is that Docker Toolbox doesn't run the Docker daemon directly on your Windows host—it uses a Linux virtual machine (typically named default) managed by VirtualBox to host the daemon. That's why running dockerd or docker daemon directly in your Windows command line throws those unsupported errors.

To limit concurrent downloads, you need to modify the Docker daemon configuration inside that Linux VM. Here's how to do it step by step:

• Access the Docker Toolbox VM shell
  Open your Docker Quickstart Terminal, or run this command in a regular Windows Command Prompt/PowerShell:

  docker-machine ssh default
  

  This will log you into the Linux VM's command line.

• Create/Edit the Docker daemon config file
  The daemon configuration is stored in /etc/docker/daemon.json. If the file doesn't exist, create it; if it does, edit it with a text editor like nano:

  sudo nano /etc/docker/daemon.json
  

  Add (or update) the file to include the concurrent downloads setting. If it's a new file, paste this valid JSON:

  {
    "max-concurrent-downloads": 1
  }
  

  If there are existing config entries (like registry mirrors), add a comma after the last entry before adding this line to keep the JSON valid.

• Restart the Docker daemon in the VM
  Apply the changes by restarting the Docker service. Depending on the VM's Linux version, use one of these commands:

  # For systemd-based VMs (most modern Toolbox versions)
  sudo systemctl restart docker
  
  # For older sysvinit-based VMs
  sudo service docker restart
  

• Verify the configuration
  Exit the VM shell (type exit), then run this command on your Windows host to confirm the setting is active:

  docker info | findstr "Max Concurrent Downloads"
  

  You should see the value set to 1.

Alternative approach (if you're creating a new VM):
If you haven't set up your Docker Toolbox VM yet, you can pass the daemon option directly during creation:

docker-machine create --engine-opt max-concurrent-downloads=1 default

This should resolve the timeout issues by limiting the number of concurrent download sessions, just like the Docker docs suggested—you just needed to target the right daemon (the one inside the VM, not your Windows host).

内容的提问来源于stack exchange，提问作者angryip