1.Eucalyptus是什么？
Eucalyptus n.桉树
Eucalyptus is a Linux-based software architecture that implements scalable private and hybrid clouds within your existing IT infrastructure. Eucalyptus allows you to use your own collections of resources (hardware, storage, and network) using a self-service interface on an as-needed basis.
桉树是一个基于linux的软件架构,用来通过计算集群和工作站弹性的实现云计算。桉树云允许您使用自己的资源的集合(硬件、存储和网络)，可以根据需要使用自己定制的服务界面。
You deploy a Eucalyptus cloud across your enterprise’s on-premise data center. Users access Eucalyptus over your enterprise's intranet. This allows sensitive data to remain secure from external intrusion behind the enterprise firewall.
你可以部署桉树云在企业的内部数据中心。用户通过内网环境访问桉树云。敏感数据保存于企业内网防火墙后，使得保证系统和数据安全。
You can install Eucalyptus on the following Linux distributions:
您可以安装桉树在Linux发行版:
- CentOS 6
- Red Hat Enterprise Linux 6
2.Eucalyptus架构
Eucalyptus is comprised of six components: Cloud Controller (CLC), Walrus, Cluster Controller (CC), Storage Controller (SC), Node Controller (NC) and an optional VMware Broker (Broker or VB).
Eucalyptus 包含六个主要组件，它们能相互协作共同提供所需的云服务。
云控器（CLC）、海象（W）、集群控制器（CC）、存储控制器（SC）、节点控制器（NC）、可选的VMware代理（Broker or VB）
Cloud Controller - 云控器
The Cloud Controller (CLC) is the entry-point into the cloud for administrators, developers, project managers, and end-users. The CLC queries other components for information about resources, makes high-level scheduling decisions, and makes requests to the Cluster Controllers (CCs). As the interface to the management platform, the CLC is responsible for exposing and managing the underlying virtualized resources (servers, network, and storage). You can access the CLC through command line tools that are compatible with Amazon’s Elastic Compute Cloud (EC2).
在 Eucalyptus 云内，这是主要的控制器组件，负责管理整个系统。它是所有用户（开发人员、项目经理、和终端用户）和管理员进入 Eucalyptus 云的主要入口。所有客户机通过基于 SOAP 或 REST 的 API 与 CLC 通信。由 CLC 负责将请求传递给正确的组件、收集它们并将来自这些组件的响应发送回至该客户机。这是 Eucalyptus 云的对外 “窗口”。
Walrus - 海象
Walrus allows users to store persistent data, organized as buckets and objects. You can use Walrus to create, delete, and list buckets, or to put, get, and delete objects, or to set access control policies. Walrus is interface compatible with Amazon’s Simple Storage Service (S3), providing a mechanism for storing and accessing virtual machine images and user data. Walrus can be accessed by end-users, whether the user is running a client from outside the cloud or from a virtual machine instance running inside the cloud.
海象允许用户存储持久数据,组织为桶和对象。你可以使用海象创建、删除和桶,或者获取和删除对象,或设置访问控制策略。海象接口兼容亚马逊的简单存储服务(S3),提供一个机制来存储和访问虚拟机映像和用户数据。海象可以由最终用户访问,用户是否正在运行一个客户端从云环境外或着从一个虚拟机实例运行在云端。
Cluster Controller - 集群控制器
The Cluster Controller (CC) generally executes on a machine that has network connectivity to both the machines running the Node Controllers (NCs) and to the machine running the CLC. CCs gather information about a set of NCs and schedules virtual machine (VM) execution on specific NCs. The CC also manages the virtual machine networks. All NCs associated with a single CC must be in the same subnet.
集群控制器(CC)通常在一台机器上执行,网络连接到两台机器上运行节点控制器(NC)和已经正在运行的云控器（CLC）。CCs收集一组信息nc和时间表的虚拟机(VM)执行特定nc。CC还管理虚拟机网络。与一个相关联的所有nc CC必须在同一个子网。
Storage Controller - 存储控制器
The Storage Controller (SC) provides functionality similar to the Amazon Elastic Block Store (Amazon EBS). The SC is capable of interfacing with various storage systems. Elastic block storage exports storage volumes that can be attached by a VM and mounted or accessed as a raw block device. EBS volumes persist past VM termination and are commonly used to store persistent data. An EBS volume cannot be shared between VMs and can only be accessed within the same availability zone in which the VM is running. Users can create snapshots from EBS volumes. Snapshots are stored in Walrus and made available across availability zones. Eucalyptus with SAN support lets you use your enterprise-grade SAN devices to host EBS storage within a Eucalyptus cloud.
存储控制器(SC)提供的功能类似于亚马逊弹性块存储(亚马逊EBS)。SC能够与各种存储系统。出口弹性块存储存储卷,可以附加一个VM和安装或访问原始的块设备。EBS卷坚持过去的VM终止和通常用于存储持久数据。EBS卷不能在虚拟机之间共享,只能在同一可用性区域访问虚拟机的运行。用户可以创建快照从EBS卷。快照存储在海象和提供可用性区域。桉树与圣支持允许您使用您的企业级SAN设备在桉树云主机EBS存储。
Node Controller - 节点控制器
The Node Controller (NC) executes on any machine that hosts VM instances. The NC controls VM activities, including the execution, inspection, and termination of VM instances. It also fetches and maintains a local cache of instance images, and it queries and controls the system software (host OS and the hypervisor) in response to queries and control requests from the CC. The NC is also responsible for the management of the virtual network endpoint.
节点控制器(NC)在任何机器上执行托管虚拟机实例。数控控制VM的活动,包括执行、检查、和终止VM实例。还获取和维护一个本地缓存实例的图像,和它的查询和控制系统软件(主机操作系统和虚拟机监控程序)在回应查询和控制来自CC的请求。数控还负责管理虚拟网络端点。
VMware Broker - VMware代理（可选）
VMware Broker (Broker or VB) is an optional Eucalyptus component, which is available if you are a Eucalyptus subscriber. VMware Broker enables Eucalyptus to deploy virtual machines (VMs) on VMware infrastructure elements. VMware Broker mediates all interactions between the CC and VMware hypervisors (ESX/ESXi) either directly or through VMware vCenter.
VMware代理(代理或VB)是一个可选的桉树组件,可以如果你是桉树的订阅用户。VMware代理允许桉树VMware基础设施上部署虚拟机(vm)的元素。VMware代理之间的所有交互介导CC和VMware虚拟机监控程序(ESX / ESXi)直接或通过VMware vCenter。
参考资料：Eucalyptus 4.0 官方文档
https://www.eucalyptus.com/docs/eucalyptus/4.0/index.html#install-guide/intro.html
https://www.eucalyptus.com/docs/eucalyptus/4.0/index.html#install-guide/euca_components.html