The VCSA Installation wizard incorrectly detects the storage deployment size of the source vCenter during migration or upgrade

Products

• VMware vCenter Server

Issue/Introduction

Symptoms:

• While trying to upgrade vCenter Server from 6.5/6.7 to 7.0 or 8.0, the upgrade wizard might incorrectly detect the storage deployment size for the source vCenter Server

         For example, the source vCenter Server was deployed with a "Normal" storage size, but the installer only offers "Large" or "X-Large" as Storage size options

         Or the source vCenter Server was deployed with a "Large" storage size, but in the installer only the "X-Large" storage configuration is available

Environment

VMware vCenter Server 8.0
VMware vCenter Server 7.0.x
VMware vCenter Server 6.7.x

VMware vCenter Server 6.5.x

Cause

This can happen when:

1. The source vCenter is deployed on a VSAN datastore with the FTT (failure to tolerate) value set to 1 or higher
   The VCSA Installer uses the Provisioned Space of the VM to configure the Storage size during deployment. On a VSAN Datastore the Provisioned Space of the VM includes the space used by its mirror/raid components and hence would be larger than the VCSA VM's used space

E.g., 173GB used space would be 346GB Provisioned space for a VCSA VM with FTT=1 (Mirror) VSAN storage policy. If the Provisioned Space is greater than the "Default" storage size for the selected VCSA size, you would only see the next larger storage options in the drop-down

2. More than 50 percent of the space available in either of the /storage/seat, /storage/db or /storage/updatemgr partitions is in use in the source vCenter Server appliance

Resolution

This is a known issue and VMware Engineering is working on a fix in a future release.

Note: While there are articles available on the Internet, describing how to shrink the disks of the VCSA after you finished the upgrade, please be aware that none of them are officially supported.

Instead, to work around the issue, you can follow the below two-stages approach during upgrade:
 

Stage 1: 

1. Open the VCSA installation wizard
2. Instead of "Upgrade", select the "Install" Option
3. In "Select Deployment Option" choose "Small" or "Medium" as the "Deployment size", similar to how the source vCenter Server was deployed. Notice that the "Storage Size" field is set to "Default"       
4. When configuring the network settings, be sure to set the IP as the temporary IP designated for the upgrade process
5. Finish stage 1 by providing other details (Note: Node type (embedded/external psc etc) has to be same as the source VC)
6. Note down the IP of the appliance and exit the installer

 

Stage 2:

1. Open VAMI UI webpage using this URL https://<New_APPLIANCE_IP>:5480
2. Login using the root credentials used in stage 1
3. Select the "Upgrade" option
4. Provide the source (old) vCenter details
5. Note: Use the IP of Source VCenter instead of the FQDN because it may not resolve in the Network and the FQDN will be pointing to the source VCenter
6. Provide the information required by the upgrade wizard
7. Start the upgrade process
8. After the upgrade is complete, connect to the Appliance and confirm all previous settings are in-place

Additional Information

Note: The same approach can be used to downsize a VCSA during the upgrade.

Consider a scenario where the VCSA was originally deployed with XLarge storage size, and the new VCSA should only have a "Large" or "Normal" storage size. However, keep in mind that the new VCSA needs to have enough storage space to accommodate the data imported from the source appliance

Also see: System Requirements for the vCenter Server Appliance