Home » VMware » VCP550D » What is the behavior of the virtual machine when it encounters an out-of-space condition?
A virtual machine has the following configuration:
Thin provisioned virtual disks
The VMFS datastore on which it resides is on a thin provisioned LUN.
The storage array is VAAI-enabled.
What is the behavior of the virtual machine when it encounters an out-of-space condition?
A. It is suspended.
B. It is gracefully shut down.
C. It is powered off.
D. It is converted to space-efficient sparse.
Correct Answer: A
Explanation/Reference:
Explanation:
A VMFS datastore that you deploy on a thin-provisioned LUN can detect only the logical size of the LUN. For example, if the array reports 2TB of storage while in reality the array provides only 1TB, the datastore considers 2TB to be the LUN’s size. As the datastore grows, it cannot determine whether the actual amount of physical space is still sufficient for its needs.
However, when you use the Storage APIs – Array Integration (VAAI), the host can integrate with physical storage and become aware of underlying thinprovisioned LUNs and their space usage.
Using thin provision integration, your host can perform these tasks:
Monitor the use of space on thin-provisioned LUNs to avoid running out of physical space. As your datastore grows or if you use Storage vMotion to migrate virtual machines to a thin-provisioned LUN, the host communicates with the LUN and warns you about breaches in physical space and about out-of-space conditions.
As the space used by the datastore increases and reaches a specified soft threshold, the host triggers a warning alarm for the datastore.
If no space is left to allocate to the thin-provisioned LUN, the following actions take place:
The storage array reports out-of-space condition to your host.
The host pauses (suspends) virtual machines and generates an out-of-space alarm.
Incorrect Answers:
B: Virtual machines are not gracefully shut down when an out-of-space condition is encountered.
C: Virtual machines are not powered off when an out-of-space condition is encountered.
D: Virtual machine disks are not converted to space-efficient sparse (SESparse) disks when an out-of-space condition is encountered.
References:
http://pubs.vmware.com/vsphere-55/index.jsp#com.vmware.vsphere.storage.doc/GUID-08CBB1F0-0CF5-4783-9A12-EB3B5A2BB830.html
http://pubs.vmware.com/vsphere-55/index.jsp#com.vmware.vsphere.storage.doc/GUID-CDF335B3-E4F5-4A27-8F1B-3629880467B7.html