Deploying a Software-Defined Data Center (SDDC) is the first step in making use of the VMware Cloud on AWS service. After you deploy the SDDC, you can view information about it and perform management tasks.
There are a number of factors to consider before deploying your SDDC.
Connected AWS account
When you deploy an SDDC on VMware Cloud on AWS, it is created within an AWS account and VPC dedicated to your organization and managed by VMware. You must also connect the SDDC to an AWS account belonging to you, referred to as the customer AWS account. This connection allows your SDDC to access AWS services belonging to your customer account.
If you are deploying a Single Host SDDC, you can delay linking your customer AWS account for up to two weeks. You cannot scale up a Single Host SDDC to a multiple host SDDC until you link an AWS account. If you are deploying a multiple host SDDC, you must link your customer AWS account when you deploy the SDDC.
AWS VPC Configuration and Availability Requirements
- The subnet must be in an AWS Availability Zone (AZ) where VMware Cloud on AWS is available. Start by creating a subnet in every AZ in the AWS Region where the SDDC will be created. That way, you can identify all AZs where an SDDC can be deployed and select the one that best meets your SDDC placement needs, whether you want to keep your VMC workloads close to or isolated from your AWS workloads running in a particular AZ. See Creating a Subnet in Your VPC in the AWS documentation for information about how to use the Amazon VPC console to create a subnet in your VPC.
- The AWS account being linked must have sufficient capacity to create a minimum of 17 ENIs per SDDC in each region where an SDDC is deployed. Although you cannot provision more than 16 hosts in a cluster, SDDC operations including planned maintenance and Elastic DRS can require us to temporarily add as many as 16 more hosts, so we recommend using an AWS account that has sufficient capacity for 32 ENIs per SDDC per region.
- We recommend dedicating a /26 CIDR block to each SDDC and not using that subnet for any other AWS services or EC2 instances. Because some of the IP addresses in this block are reserved for internal use, a /26 CIDR block is the smallest subnet that can accommodate the 33 addresses required for an SDDC.
- Any VPC subnets on which AWS services or instances communicate with the SDDC must be associated with the main route table of the connected VPC. Use of a custom route table or replacement of the main route table is not supported.
- If necessary, you can link multiple SDDCs to a VPC as long as the VPC subnet used for ENI connectivity has a large enough CIDR block to accommodate them. Because all SDDCs in a VPC use the same main route table, make sure that network segments in those SDDCs don't overlap with each other or the VPC's primary CIDR block. Workload VMs on routed SDDC networks can communicate with all subnets in the VPC's primary CIDR block, but are unaware of other CIDR blocks that might exist in the VPC.
Single Host SDDC starter configuration for VMware Cloud on AWS
You can jump start your VMware Cloud on AWS experience with a Single Host SDDC starter configuration. This is a time-limited offering designed for you to prove the value of VMware Cloud on AWS in your environment. The service life of a Single Host environment is limited to 30 days. At any point during the service life of a Single Host SDDC, you can scale it up to a production configuration with three or more hosts with no loss of data. If you don't scale up the Single Host SDDC before the end of the service life, the SDDC is deleted along with all the workloads and data it contains.
Stretched Clusters for VMware Cloud on AWS
You can create an SDDC with a cluster that spans two availability zones. A stretched cluster uses vSAN technology to provide a single datastore for the SDDC and replicate the data across both availability zones. If service in one availability zone is disrupted, workload VMs in the SDDC are brought up in the other availability zone.
The following restrictions apply to stretched clusters:
- The linked VPC must have two subnets, one in each AZ occupied by the cluster.
- A given SDDC can contain either standard (single availability zone) clusters or stretched clusters, but not a mix of both.
- You can't convert a stretched cluster to a standard cluster, or vice versa.
- You need a minimum of six hosts (three in each AZ) to create a stretched cluster. Hosts must be added in pairs.
For additional limitations that can affect stretched clusters, see Configuration Maximums for VMware Cloud on AWS.
Connecting to the SDDC and Configuring SDDC Networks
Before you can migrate your workload VMs and manage them in VMware Cloud on AWS, you'll need to connect your on-premises data center to your SDDC. You can use the public Internet, AWS Direct Connect, or both for this connection. You'll also need to set up one or more Virtual Private Networks (VPNs) to secure network traffic to and from your SDDC, and configure SDDC networking and security features like firewall rules, DNS, and DHCP. The VMware Cloud on AWS Networking and Security guide has more information about how to do that.