To upgrade NSX Data Center for vSphere in a cross-vCenter environment, you must upgrade the NSX components in the order in which they are documented in this guide.
NSX Data Center for vSphere components must be upgraded in the following order:
Primary NSX Manager appliance
All secondary NSX Manager appliances
NSX Controller cluster
The upgrade process is managed by the NSX Manager. If the upgrade of a component fails or is interrupted and you need to repeat or restart the upgrade, the process begins from the point at which it stopped; it does not start over from the beginning.
The upgrade status is updated for each node and at the cluster level.