Create an availability zone plan

Availability zones (AZs) are logical groups of resources available for a service. As a cloud administrator, you manage the resources available for organizations by assigning them to different AZs.

Availability zone types

UIS Cloud offers compute AZs and storage AZs to isolate compute resources and storage resources, respectively.

• Compute AZ—A compute AZ is identical to a compute resource pool. It contains a group of virtualized physical servers (hosts) in redundancy mode for service backup and recovery. Developed based on OpenStack Nova, the compute AZs are also called Nova AZs. If you use a Nova AZ for different storage services, you can assign different compute AZ alias to that Nova AZ to identify those storage services. VMs can migrate between hosts in the same compute AZ when host failure occurs.

• Storage AZ—A storage AZ is identical to a storage resource pool. It contains a group of storage spaces for virtual cloud disk services. When you create a cloud disk, you must select a storage AZ. Then, you can mount the cloud disk to a VM. Developed based on OpenStack Cinder, the storage AZs in UIS Cloud are also called Cinder AZs. If you use a Cinder AZ for different storage services, you can assign different storage AZ alias to that Cinder AZ to identify those storage services.

Restrictions and guidelines

Create a compute AZ for each site (also called a compute node). Assign a unique storage AZ name to each compute AZ.

Best practices of AZ planning

Use the following principles when you plan the capacity and assignment of AZs for organizations as a cloud administrator:

• Compute first—Availability of compute resources is the top concern of users. Plan compute AZs before you plan storage AZs.

• Be homogeneous—Features and software images vary depending on virtualization platform. As a best practice, make sure an AZ contains only resources from one type of virtualization platform.

• One compute AZ for one site—Create one compute AZ for one site. Each site is a compute node abstracted from one cluster or one host pool in a virtualization platform.

• One storage AZ for one compute AZ—Storage resource pools are managed on the virtualization platforms. To avoid unexpected issues, create one storage AZ for each compute AZ.

 

In UIS Cloud, a compute resource pool might be one of the following: ·          A UIS Manager cluster. ·          A cluster or a host pool in CAS. ·          A VMware ESXi cluster.

 

AZ planning example

A company has the following virtualization platforms and compute resources:

• Virtualization platforms—One H3C UIS Manager platform, one H3C CAS platform, and one VMware platform.

• UIS compute resources—A cluster that contains 16 hosts. The cluster name is UISCO.

• CAS compute resources—Two host pools that each contain 16 CVK hosts. The host pool names are HPool1 and HPool2.

• VMware compute resources—A cluster that contains 16 hosts. The cluster name is Cluster1.

• The company has departments Org1, Org2, Org3, Org4, and Org5. Each department is an organization in UIS Cloud.

Assign UIS cluster UISCO to department Org1, CAS host pool HPool1 to department Org2, CAS host pool HPool2 to department Org3, and VMware ESXi cluster Cluster1 to Org4 and Org5.

Table-1 shows the AZ plan for the company. Each department can request resources from the AZs assigned to them.

Table-1 AZ plan

Item	Org1	Org2	Org3	Org4	Org5
Virtualization platform	UIS Manager	CAS		VMware
Hosts	16	16	16	16
Compute resource pool	UISC0	HPool1	HPool2	Cluster1
Storage AZ	Cinder1	Cinder2	Cinder3	Cinder4
Compute AZ	Nova1	Nova2	Nova3	Nova4
Storage AZ alias	Org1_storage	Org2_storage	Org3_storage	Org4_storage	Org5_storage
Compute AZ alias	Org1_compute	Org2_compute	Org3_compute	Org4_compute	Org5_compute