Information Technology Reference
In-Depth Information
The last topic we'll cover before moving on to more hands-on topics is the vSphere
Storage APIs.
Uncovering the vSphere Storage APIs
Formerly known as the vStorage APIs, the vSphere Storage APIs aren't necessarily application
programming interfaces (APIs) in the truest sense of the word. In some cases, yes, but in other
cases, they are simply storage commands that vSphere leverages.
There are several broad families of storage APIs that vSphere offers:
vSphere Storage APIs for Array Integration
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vSphere APIs for Storage Awareness
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vSphere Storage APIs for Site Recovery
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vSphere Storage APIs for Multipathing
vSphere Storage APIs for Data Protection
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Because of the previous naming convention (vStorage APIs), some of these technologies are
more popularly known by their acronyms. Table 6.2 maps the well-known acronyms to their
new ofi cial names.
Table 6.2:
vSphere Storage API acronyms
Well-Known Acronym
Official Name
VAAI
vSphere Storage APIs for Array Integration
VASA
vSphere APIs for Storage Awareness
VADP
vSphere Storage APIs for Data Protection
In this topic, for consistency with the community and the marketplace, we'll use the well-
known acronyms to refer to these technologies.
As we mentioned previously, some of these technologies are truly APIs. The Storage APIs
for Multipathing are the APIs that VMware partners can use to create third-party MPPs, SATPs,
and PSPs for use in the PSA. Similarly, the Storage APIs for Site Recovery encompass the actual
programming interfaces that enable array vendors to make their storage arrays work with
VMware's Site Recovery Manager product, and the Storage APIs for Data Protection (VADP) are
the APIs that third-party companies can use to build virtualization-aware and virtualization-
friendly backup solutions.
There are two sets remaining that we haven't yet mentioned, and that's because we'd like to
delve into those a bit more deeply. We'll start with the Storage APIs for Array Integration.
Exploring the vSphere Storage APIs for Array Integration
The vSphere Storage APIs for Array Integration (more popularly known as VAAI) were i rst
introduced in vSphere 4.1 as a means of ofl oading storage-related operations from the ESXi
hosts to the storage array. Although VAAI is largely based on SCSI commands ratii ed by the
