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VMware integrations
21 Dell EMC PowerVault ME4 Series and VMware vSphere | 3922-BP-VM
7 VMware integrations
The ME4 Series array has several integrations and touchpoints with the VMware vSphere ecosystem. Like
the vSphere Web Client plug-in, some are more visible then others, such as the VAAI primitives in the
firmware. However, a clear understanding of the functionality and benefits they provide is vital to efficient
virtual-environment design.
These integrations and touchpoints include VMware vStorage APIs for Array Integration (VAAI) and VMware
Storage I/O Control (SIOC).
7.1 VMware vStorage APIs for Array Integration
VMware vSphere recognizes that the underlying storage it is using may be capable of more than just storing
data. Through its storage partners (including Dell Technologies), VMware developed a set of APIs which
leverage the SCSI T10 specification to use the advanced capabilities that exist in intelligent storage products
such as ME4 Series arrays.
This set of APIs is referred to as vStorage APIs for Array Integration (VAAI) and includes the following SCSI
primitives:
• Full copy
• Block zeroing
• Hardware-assisted locking
• Thin provisioning space reclamation
7.1.1 Full copy
A common day-to-day IT task involves deploying servers to support new business applications. Virtualization
changed this from a labor-intensive task of racking a server and installing the operating system to a simple
task that required only a couple of mouse clicks to deploy a virtual machine from a preconfigured template.
While this change has resulted in substantial time savings, there was still a significant amount of time spent
watching the progress bar as the virtual machine deployed. Traditionally, the process of deploying a virtual
machine involved all of its data being read from the array, across the network to the ESXi host, and then
written back across the network to the array. This placed a non-production workload on both the network and
the ESXi host, in addition to the production workload of the running environment. Now, with the full copy
primitive, ESXi can offload this task to the array where it can be completed much more efficiently, with a
significant workload reduction for the ESXi host and the network. The benefits of full copy do not end with
deploying virtual machines from templates. They also extend to virtual-machine tasks such as Storage
vMotion, and virtual machine cloning.
7.1.2 Block zeroing
Fault-tolerant virtual machines require VMDKs that are eager-zeroed thick. These differ from standard thick or
thin VMDKs in that the blocks are zeroed out at the time that the VMDK is created. For large disks, this can
take a significant amount of time as each zero is written from the server to the array, and an acknowledgment
of each write is sent back from the array to the server. With the block zeroing primitive, the ESXi host offloads
to the ME4 Series array the task of zeroing out the blocks, and permits the host to continue creating the fault-
tolerant virtual machine while the storage completes the zeroing task in the background. By offloading the
block zeroing to the ME4 Series array, fault-tolerant virtual machines can be created much faster.