1) Add Xen hosts
2) Create Primary storage in the cluster. This should create Storage respository for the Xenserver
3) Create compute offering to create root disk on the created primary storage
4) Create an instance.
5) Once the VM is UP.
6) Check storage statistics on CloudStack (primary storage) and on Xenserver (storage repository)
There is a variance in the allocated size shown on CloudStack Primary storage and associated Xen Storage repository.
I used Debian based system VM template to create the VM.
Disk Total 10 GB
Disk Allocated 5.87 GB
4.2 GB used of 10 GB (2.9 GB allocated)