There isn't a migration guide since you're supposed to spawn a new cluster and move your workloads there by exporting the images and redefining the templates to benefit from the new optimized defaults.
The process can be summarized as following:
- Deploy a 11.0 node to start the new cluster (this can be done, if you have enough spares, using a node from your old cluster)
- Use the 10.3.2 cluster's Service Portal to sync via CIFS the latest datastore snapshot to the new cluster upload folder
- Stop a VM, snapshot, sync the differences (move the image to the new cluster)
- Import the image you just synced from the 10.3.2 cluster in the 11.0 web GUI defining the path under /upload folder
- Define a template and eventually a virtual network for it and instantiate it on the 11.0 cluster
repeat 3,4,5 for all your VMs and as you free a node from your 10.3.2 cluster you can shut it down, flash with the new 11.0 image and join it to the new cluster.
Other option, if you can afford larger downtime, to stop all the VMs, do a snapshot, sync all the snapshot at once to the upload folder on a newly provisioned node, import images and define templates and virtual networks at once, and mass-convert all the old nodes to 11.0 by flashing the NodeWeaver OS image and join them to the new cluster.