We are in the middle of migrating from ESX 5.5 to 6.5 and also to a new 3rd party backup solution. Currently we use VSC 6.2.1 for vmware backups on the esx 5.5 clusters. We want to upgrade ONTAP from 9.2p1 to 9.3p1, can this be done without impacting backups on our 5.5 clusters that use vsc 6.2.1?
You'll want to verify this using the Interoperability Matrix Tool, but we were playing around with various upgrade paths, and found that VSC backups will get affected by an upgrade to ONTAP 9.3. ONTAP 9.3 requires VSC 7.1 or better, and VSC 7.1 no longer does native backups ... you'll need SnapCenter, which costs something or other.
Unfortunately VSC 6.2.1 is not tested and supported with ONTAP 9.3. As the other poster indicated, ONTAP 9.3 is supported with VSC 7.1. You can use the IMT (https://mysupport.netapp.com/matrix/#welcome) to explore supported combinations quickly. Pick Storage Solution Search, select Virtual Storage Console, and then use the checkboxes to see what components are unsupported (grey) and supported (black).
FYI, End of Version Support was recently posted for VSC 6.2.X: