I am seeing some strange things storage wise in vCD 5.5. I some of our vOrgs the numbers just do not add up. For instance in one vOrg they are allocated 750GB of storage. There are 4 vApps each with 1 VM and the total of the disk sizes is 231GB thin provisioned. When they try to add a 5th VM they get a message that there is not enough disk space available. When I look at the Storage Policy it says 750GB. When I right click on the storage policy and select properties it shows 42.34% used of 746GB. When I look at the properties of the datastore it shows a total capacity of 720GB, a used capacity of 304GB, an available capacity of 415GB, a provisioned capacity of 1, 330GB, and requested storage of 746GB. Looking at the Org VDC it shows 746GB used of 750GB allocated.
Looking at the datastore in the vCenter client shows 304GB used, 415GB free and a capacity of 720GB. It also shows 17 VMs.
We are seeing this type of thing in some vOrgs but not others. How does vCloud manage storage?
Assuming this is a single datastore:
Capacity = 720GB
Used = 304GB
Available = 415GB
Red Threshold= 108GB (estimate)
Org vDC Storage Policy = 750GB allocation, of which 746GB is used (4 GB free)
not this value is a fictional number. it's how many GB of VMDK is provisioned in VMs inside this Org & Profile/Policy. There is NO relation to actual free space here.
Thin/Fast provisioning is probably messing with your head a little (hence why used is so low and provisioned is so high).
Just know, when I create a VM:
Check 1: will the VM fit within the storage policy? e.g. the entire VM is smaller than 4 GB including swap etc
- I'm pretty sure this will fail based on your setup. If there was more free move on
Check 2: can the VM fit inside a single datastore's free space. Free = Available - Red Threshold
415 - 108 = 307GB
Is the VM smaller than 307 GB? yes, then this datastore is eligible for provisioning.
there are other checks, but these are related to space requirements.