Sample config for availability zone and host group
The IBM® Cloud Infrastructure Center supports, both, the availability zone and the host group to create logical groupings of compute nodes. After the compute nodes are added to the IBM Cloud Infrastructure Center, the cloud administrators need to plan whether they need multiple availability zones and multiple host groups besides the Default Group availability zone and the Default Group host group. Then, the cloud administrators and the project administrators can select the availibility zone and the host group(via compute template) to create a deploy template for the self-service users. For more information about the availability zone, the host group and the compute template, please refer to Availability Zone, Host group and Compute Template.
In this sample, the steps to create an availbility zone and a host group, as well as the create deploy template are outlined and the typical scenarios for deployment are shown. Harry is the cloud administrator in the following figures.
Steps to use AZ/Host Group to create deploy template:
1.Figure1 shows the cloud administrator’s initial cloud environments to be managed. There are eight compute nodes located in two data centers. Assume these compute nodes have different storage types, either ECKD or SCSI storage.
Figure1
2.After adding these compute nodes on the management node, these compute nodes belong to the Default Group host group and the Default Group availability zone, which is shown in Figure2.
Figure2
3.On the WebUI, navigate to Host Groups tab, click create button, input host group name, availability zone and aggregate instance extra specs respectively. Please note that input aggregate instance extra specs only when you want to place a virtual machine to a specific host group during deployment, and you need to create a compute template that has the same extra specs to match the host group.
Figure3
4.In this example, input site1-eckd-group-1 as the host group name, input site1 as the availability zone for the host group and {"eckd": "true"} for the aggregate instance extra specs, then add host1 and host2 to the host group, Figure4 shows the status after that.
Figure4
5.Similar to site1-eckd-group-1, create site1-scsi-group-1, site2-eckd-group1, site2-scsi-group-1 with corresponding availability zone and aggregate instance extra specs input, add hosts into correct host groups, Figure5 shows the status after that.
Figure5
6.This step is optional and only necessary if you want to place a virtual machine to a specific host group during deployment. Figure6 shows the create compute templates page. On the create compute templates page, input {"aggregate_instance_extra_specs:eckd":"true"} in the Aggregate Instance Extra Specs so that it can match host group site1-eckd-group-1.
Figure6
7.In create deploy template page, project admin can select Deploy target and Compute template. For deploy target, you can either select an availability zone or a host as the deploy target. For Compute template, select compute template(flavor) with extra_specs only when you want to place a virtual machine to a specific host group during deployment.
Figure7
Typical scenarios for deployment:
In the following figures, from left to right it shows the deployment flow: the project administrator first creates the deploy template. Then the self-service user uses the deploy template to deploy the virtual machines. Finally after the deployment, the virtual machines' status.
Scenario1: the deploy template for users to deploy VMs with eckd in site1. In the create deploy template page, selects site1 for the availability zone, as the virtual machine is required to be placed on the host group with eckd. Select "eckdflavor" for the compute template. In the deployment page, use the deploy template to deploy two virutal machines, the two virtual machines are placed on the hosts in the site1-eckd-group-1 hostgroup.
Figure8
scenario2: the deploy template for users to deploy VMs in site1. In the create deploy template page, select the site1 for the availability zone. There is no requirement for the virtual machines to be placed on a specific hostgroup. Selecting the compute template without any extra_specifications is fine. In the deployment page, use the deploy template to deploy two virutal machines. The two virtual machines are placed on the hosts in site1. The hosts that are selected depend on the cpu/memory/disk resources status of these hosts.
Figure9
