The xsibackup options --replica=cbt for replicating a VM and --options=R for registering the replicated VM can only be used if the VM is replicated to a destination path that is either mounted by the same ESXi host or, in case of using a remote path, when the destination system is also an ESXi host. This is quite clear, as registration of the replicated VM requires an ESXi host.
At present, it is already possible to register the replicated VM, even if it is stored on a remote system like a Synology NAS, as long as the disk at the remote system is mounted at the local ESXi host, for example by using NFS.
So it is possible to replicate and register the replicated VM on the same ESXi host, although the files are remote to the ESXi host.
I would like to improve performance by performing --replica=cbt by specifying the remote path and using xsibackup executed on the Synology NAS. However, once I specify the remote path, the remote xsibackup cannot register the replicated VM as the Synology NAS is not an ESXi host.
Therefore, I would like to process the --options=R in a separate step, after having performed the replication via remote path, were I specify the path to the replicated VM via the NFS drive of the Synology NAS mounted at the ESXi host.
Would this be feasible?
We have no plans to offer that feature. It is highly dependent on the target OS and too many assumptions have to be made to implement it. We do not consider this feature request to be feasible.