vSAN 7平台组件架构解析

1、vSAN 7平台组件架构解析2The main vSAN architecture components are:3vSAN Architecture Analogy: Building a House4The CLOM process runs on every vSAN node:ilable resources.Itvalidates that objects can be createdbased on policiesandavaItis responsible for object compliance.Itdefines the creation and migration of

2、objects.It distributes loads evenly between the vSAN nodes.It is responsible for proactive and reactive rebalancing.You manage the CLOM process with the /etc/init.d/clomd status|stop|start|restart command.CLOM and Its Role: Architect5ideThe DOM runs on each host in a vSAN cluster.The DOM process inc

3、ludes:Managing object availability and initial I/O requestsReplicating and coordinating I/O to hosts where components resDetermining object accessibilityReceiving instructions from the CLOM and the DOMs running on other hosts in the vSAN clusterInstructing the LSOM to create local components of an o

4、bject:DOM services on the hosts of a vSAN cluster communicate to coordinate the creation of components.All DOMs in a vSAN cluster resynchronize objects during a recovery.DOM and Its Role: Contractor (1)6Each object has a DOM owner, a DOM client, and a DOM component manager.DOM Client:Processes the I

5、/O generated by a VMRuns on every node that contains VMsForwards I/O to the DOM Owner DOM Owner:Receives I/O requests from the DOM ClientDetermines object accessibilityReplicates I/O based on the objects RAID layout and determines in which components the data blockresidesForwards the I/O to the DOM

6、Component Manager where the components reside DOM Component Manager:Interacts with the LSOM locally to commit the I/O to diskDOM and Its Role: Contractor (2)7The LSOM performs the following functions:Creates the local components as instructed by the DOMProvides read and write bufferingPerforms the e

7、ncryption process for the vSAN datastoreReports unhealthy storage and network devicesPerforms I/O retries on failing devicesInteracts directly with the solid-state and magnetic devicesPerforms solid-state drive log recovery when the vSAN node bootsLSOM and Its Role: Worker8icesThe CMMDS performs the

8、 following functions:Provides topology and object configuration information to the CLOM and the DOM as requestedRecords the owners of the objectsInventories all items, such as hosts, networks, and devStores object metadata information, such as policy-related information on an in-memory databaseDefin

9、es the Master, Backup, and Agent cluster roles:The backup host accelerates the process of convergence if the master host fails.Roles are decided at the time of cluster discovery.Communication between the master host and other hosts occurs every second.Updates are exchanged through the RDT.CMMDS and

10、Its Role: Project Manager9RDT is a network protocol for the transmission of vSAN traffic.RDT and Its Role: Delivery Truck10When it receives a request to create an object, the CLOM determines whether the objectcan be created with the selected VM storage policy.If the object can be created, the CLOM i

11、nstructs the DOM to create the components.Component Interaction: Architect and Contractor11During component creation, the DOM, CLOM, and LSOM have the following interactions:The DOM decides what components are created locally.The DOM instructs the LSOM to create the local components. The LSOM intera

12、cts at the drive layer and provides persistent storage. The DOM interacts with the LSOM across the local hosts.If components are required on other nodes, the DOM interacts with the DOM instance onthe remote node.Component Interaction: Contractor and Worker12The DOM and the CLOM consult the CMMDS:To get information about available resources in the clusterTo learn about the topology and the object configurationComponent Interaction: Architect, Contractor, and Project Manager13St