Upgrading is a multistage process in which procedures must be performed in a particular order. If you follow the suggested process, you can help ensure a smooth upgrade with a minimum of system downtime.

Caution

VMware recommends that you read about the upgrade process before attempting to upgrade. If you do not follow appropriate safeguards, you might lose data and lose access to your servers. Without careful planning, you might incur more downtime than is necessary.

You must complete the upgrade process in a specific order. If you do not complete each upgrade stage before moving on, you can lose data and server access. Order is also important within each upgrade stage.

Generally, you can perform the upgrade process for each component in only one direction. For example, after you upgrade to vCenter Server, you cannot revert to VirtualCenter 2.x. With appropriate backups and planning, you can restore your original software records.

You can take any amount of time to complete each of the upgrade procedures. However, keep in mind the following considerations:

You must complete one procedure before you move to the next procedure.

Some major procedures include minor substeps. Follow the directions within each procedure regarding the required sequence of minor substeps.

Because certain commands can simultaneously upgrade more than one stage, VMware recommends that you thoroughly understand the irreversible changes at each stage before you upgrade your production environments.

To ensure that your datacenter upgrade goes smoothly, you can use vCenter Update Manager to manage the process for you.