The core components of a CloudStack implementation are:Hosts – Hosts are servers from at least one of the supported virtualization providers. CloudStack fully supports hosts from multiple providers, but does not convert VM images from one hypervisor type to another. Depending on the hypervisor, a “host” may be a higher level concept. For example, in XenServer a CloudStack “host” is equivalent to a XenServer resource pool and the “host” entry is the pool master.Primary Storage – Primary storage is the hypervisor level storage containing the deployed VM storage. Primary storage options will vary by hypervisor, and depending upon the hypervisor selected, CloudStack may impose requirements upon it.Cluster – Host groups are combined into Clusters which contain the primary storage options for the Cluster. Primary storage isn’t shared outside of a Cluster. In the case of CloudStack, a Cluster in of itself does not imply modification of any clustering concept within the hypervisor. For example, in XenServer a resource pool is a host to CloudStack, and CloudStack does not create a super set of Cluster functionality for XenServer. Pod -- Host groups are combined first into Clusters and then into Pods. For many customers, a pod represents a high level physical concept like a server rackNetwork – Network is the logical and physical network associated with service offerings. Multiple concurrent network service offerings and topologies can be supported within CloudStackSecondary Storage – Secondary storage is the storage system used for template and ISO management. It also is where snapshot events occur.Zone – A zone is a collection pods to form some level of service availability. While Amazon EC2 defines an availability zone as a data center, CloudStack keeps the concept more abstract allowing cloud operators to have multiple availability zones within a given data center.Management Server Farm – The CloudStack management server farm is a grouping of CentOS/RHEL CloudStack servers forming a web farm, with an underlying MySQL cluster database. The management server farm can manage multiple Zones, and can be virtualized.
2. Copyright 2009 Trend Micro Inc.AgendaDesign ConsiderationsDesign GuidelinesDC Cloud High Level ArchitectureGlobal Cloud High Level Architecture
3. Copyright 2009 Trend Micro Inc.Design ConsiderationsService AssuranceHigh AvailabilitySecure Tenant segregation Data Center Scalability through ModularInfrastructure
4. Copyright 2009 Trend Micro Inc.Service AssuranceDifferentiated Service Requirements for Differentservice types: Production (Critical),Development/Testing, and Staging. Differentiated Service levels are fulfilled withmodular POD designs, with Tier1 resourceguaranteed in critical POD while Tier2 resourceallow cost reduction. Differentiated Service profile is cost efficient inprivate cloud environment.
5. Copyright 2009 Trend Micro Inc.High AvailabilityInfrastructure high availability through datacenter,availability zone, POD, Cluster, and physicalredundancy. Infrastructure is ready for manual or automaticdisaster recovery plans.Public cloud can be an option for disasterrecovery.Bursting traffic can be served by public cloud toprevent over provision in private cloud.
6. Copyright 2009 Trend Micro Inc.Secure Tenant SegregationSecure Tenant Segregation through segregationof network, compute and storage.Segregate tenants/services with PODs oravailability zones deployments.Could infrastructure component outage will notimpact any service…. Or only impact singleservice.Secure Tenant Segregation did not coverapplication dependency. For example, ERS canimpact HES in application level.
7. Copyright 2009 Trend Micro Inc.Datacenter Scalability throughModular InfrastructureElasticity can be scaled with vertical scale inside aPOD or horizontally scale across PODs,Availability Zones, and Datacenters.A modular design unit- POD is the basic buildingblock.A POD contains its delectated infrastructurenetwork, compute node, and storage node andcan share VM networks within an availability zone.POD forms availability zone, and thendatacenters.POD can be migrated and repurposed.
9. Copyright 2009 Trend Micro Inc.Loosely Coupled, Stateless, andFail-in-Place ComputingOld Paradigms of web services are moreimportant in cloud computing as Cloud is bynature very dynamic.Application and infrastructure components need tobe loosely coupled, stateless, and fail-in-placewith no impact to service.Same paradigms applied to cloud platformhardware, the hardware should be looselycoupled, stateless, and be ready to fail with noimpact/minimal impact.Asynchronous tasks and messaging system arethe two keys for Loosely Coupled Architecture.
10. Copyright 2009 Trend Micro Inc.Loosely Coupled, Stateless, andFail-in-Place ComputingCloud architecture is loosely coupled withmanagement servers, compute nodes, storagenodes and DB nodes. Management servers, compute nodes, storagenodes, are stateless. The transaction traffic can beserved by any nodes in the Cloud.Any cloud components are designed to be hitlessand be ready to fail-in-place with no impact to theservice.Users submit asynchronous Cloud jobs like createinstance with instant response and performance.Background jobs runs in each components to fulfillthe user requests.
11. Copyright 2009 Trend Micro Inc.Horizontal scalingIt is more challenge to scale up (physical limit)than scale out (logical limit).Cloud computing has its advantages in horizontalscaling.The horizontal scaling capability does not limit to asingle Cloud. It can be hybrid or even scaling topublic Cloud.Data Physics ( time to move data/meta dataacross Cloud) needs to be considered when“Surge computing” to Public Cloud. (Datareplication to public cloud before disaster mayintroduce cost)
12. Copyright 2009 Trend Micro Inc.ParallelizationParallelization works hand in hand with HorizontalScaling.Parallelization cancel the impact of the fail rate ofeach component to increase availability andperformance.Application client intelligence, load balancer, andglobal server load balancer, are technologies toachieve parallelization. Among the above three, application clientintelligence has lowest CAPEX and OPEX of theservice availability, so it is most preferred by theimplement Parallelization.However, the most common easy way forparallelization is hardware/software load balancer.
13. Copyright 2009 Trend Micro Inc.• Hosts• Servers onto which guest VM services will beprovisioned• Primary Storage• VM storage• Cluster• A grouping of hosts and their associated storage• Pod• Collection of clusters• Network• Logical network associated with service offerings• Secondary Storage• Template, snapshot and ISO storage• Zone• Collection of pods, network offerings and secondarystorage• Management Server Farm (mgmts. + DBs)• Responsible for all management and provisioningtasksCore CloudStack ComponentsZoneCloudStack PodClusterHostHostNetworkPrimaryStorageVMVMCloudStack PodClusterSecondaryStorage
15. Copyright 2009 Trend Micro Inc.CloudStack Regional ArchitectureManagement server deployment required tohave very low latency to DB servers withinthe same region. It is recommended todeploy multiple separate managementservers when crossing multiple crossregions.