Veeam's RnD team has extensively tested with Veeam Backup & Replication 12.1.2 (build 12.1.2.172) and has determined that it is functional with vSphere 8.0 U3; however, the following limitations apply:
The automatic exclusion of vCLS VMs does not occur after upgrading to vSphere 8.0 U3. This automatic exclusion feature, first introduced in Veeam Backup & Replication 10, fails to function because vSphere 8.0 U3 changed the VM type identifier for vCLS VMs.
Update: Veeam Backup & Replication 12.2 was released on 2024-08-28 and includes a new method for identifying and automatically excluding vCLS VMs.
Due to a lack of access to NSX-T 4.2.0, compatibility of NSX-T 4.2.0 and vSphere 8.0.3 has not been tested with Veeam Backup & Replication.
Update: Final testing has been completed, and support for NSX-T 4.2.1 is now fully provided starting in Veeam Backup & Replication 12.3.1.
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