2.8. 使用设备插件通过 pod 访问外部资源

设备插件提供一致且可移植的解决方案，用于在集群中消耗硬件设备。设备插件通过一种扩展机制提供对这些设备的支持，从而使这些设备可供容器使用，提供这些设备的健康检查，并安全地共享它们。

设备插件是在节点( kubelet的外部)上运行的 gRPC 服务，负责管理特定的硬件资源。任何设备插件都必须支持以下远程过程调用(RPC)：

service DevicePlugin {
      // GetDevicePluginOptions returns options to be communicated with Device
      // Manager
      rpc GetDevicePluginOptions(Empty) returns (DevicePluginOptions) {}

      // ListAndWatch returns a stream of List of Devices
      // Whenever a Device state change or a Device disappears, ListAndWatch
      // returns the new list
      rpc ListAndWatch(Empty) returns (stream ListAndWatchResponse) {}

      // Allocate is called during container creation so that the Device
      // Plug-in can run device specific operations and instruct Kubelet
      // of the steps to make the Device available in the container
      rpc Allocate(AllocateRequest) returns (AllocateResponse) {}

      // PreStartcontainer is called, if indicated by Device Plug-in during
      // registration phase, before each container start. Device plug-in
      // can run device specific operations such as reseting the device
      // before making devices available to the container
      rpc PreStartcontainer(PreStartcontainerRequest) returns (PreStartcontainerResponse) {}
}

设备插件示例