# Component

### 1. Core

> 调度器核心

* 无状态
* 生成编排方案
* 并发进行部署

### 2. Agent

> Node 上的控制器

* 资源消耗低
* 负责容器检查
* 获取 Metrics 发送到远端
* 转发日志

### 3. ELB (Eru load balancer)

> 7 层动态服务发布

* 基于 [Openresty](https://openresty.org/en/)
* 本身也是 Eru 应用之一
* 通过指定的 Redis 进行发布工作
* 应用上下线过程中保证流量平稳切换

### 5. Cli

> 命令行工具

* 提供类似于 AWS Lambda 子命令
* 通过 cli 操控集群本身
* 通过 cli 可以在初始化集群之后进行集群自举

### 6. Minions

> A calico libnetwork plugin port

* Calico libnetwork plugin 不支持 docker engine
* 采用最新的 libcalico + etcdv3 实现
* 行为和 calico-cni plugin 一致
* 支持 bird 的最新版本和其特性
* 支持原生 fixed IP 特性

### 7. Barrel

> A docker daemon wrapper

* Docker wrapper for fixed IP feature
* 原生区分了 stop/remove 行为

### 8. Yavirt

> Yet another virt daemon

* 基于 QEMU-KVM 的虚拟机 runtime
* 支持多种行为操作, 比如 execute command, remote console
* 支持 Calico 网络的集成
* 支持镜像一键式打包上传到 VM Image Hub


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