Multisite configuration for VCF for Classic - Automated
IBM Cloud® for VMware Solutions allows instances to be deployed across different locations and have them up and running in a short time.
Multisite deployment components
A multisite deployment consists of the following components.
- Primary instance - The primary VMware Cloud Foundation for Classic - Automated instance has the following configuration:
- Microsoft® Active Directory™ (AD) and DNS (Domain Name System) root domain
- vCenter Server located in domain with instance-specific name
- SSO (single sign-on) domain
- SSO site name
- vCenter Server Appliance with embedded Platform Services Controller (PSC)
- Secondary instance or instances - One or more secondary Automated instances, linked to the primary instance, with the following configuration:
- SSO site name
- Same DNS domain as primary instance
- DNS and AD replication setup between the AD virtual machines on the primary and secondary instances
- VMware vCenter Server® on the secondary instances is set up with Enhanced Linked Mode (ELM) to the vCenter Server on the primary instance
VCF for Classic - Automated multisite deployment
The multisite configuration feature uses a hub and spoke topology with a primary site and a maximum of seven secondary sites. A single layer of sites is supported, that is, you cannot configure subsequent sites that are linked to other secondary sites. You can have a total of 128 VMware ESXi™ servers in a multisite configuration across all instances.
If your configuration requires a multisite deployment with more than 128 ESXi servers, open an IBM Support ticket by following the steps in Getting help and support.
The following graphic depicts the overall view of the VCF for Classic - Automated multisite deployment.
The model contains the following layers:
- Primary instance - To deploy the first instance in a multisite configuration, you define that instance as primary during the instance order process.
- Secondary instances - In a multisite configuration, you define the instances that are attached to the primary instance as secondary instances during the order process.
You can assign only one secondary instance to a primary instance at a time. You cannot assign multiple secondary instances to a primary instance at the same time. To do that, you must go through the order process again and select the previously defined primary instance as a primary instance for the secondary instance. You must repeat the process for all secondary instances that you want to create.
You can have a maximum of 15 (one primary and 14 secondary) instances that are deployed in a multisite configuration.
Deleting Automated instances that are part of a multisite configuration requires special planning. For more information, see Deleting Automated instances in a multisite configuration.