VMware Storage Integration Explained
As an architect, I talk to many vendors and customers, and often the conversation is about what makes one storage vendor better than another for VMware. I’m not going to focus on performance and array types of features, but what I do want to cover is the integration points that storage vendors can offer between their products and VMware.
When it comes to VMware storage integrations, it comes down to two questions. First, can the storage device do what others can– and if so, then what are the table stakes? Second, what integrations can a vendor offer that’s unique to that vendor? And to qualify as a VMware integration point, I think it must be something that improves intelligence, manageability, performance, or automation.
VMware Storage Integration Points
vSphere API for Array Integration (VAAI): VAAI has been around for a few years now. Simply put, for a short list of function, vSphere is able to let the storage array execute the activity and them report back. This is essentially moving the burden from the vSphere host to the storage for these functions. This can increase speed and performance and also reduce provisioning times. There are two sets of VAAI primitives available, one for block storage and another for NFS storage. For a deeper look into VAAI function read the VMware VAAI whitepaper. For me, this is table stakes for storage vendors to be considered competitive. In today’s marketplace, if you cannot offer VAAI support you will be pretty low on my list.
vSphere APIs for Storage Awareness (VASA): VASA was released with vSphere 5.0, and it’s there to identify storage capabilities. The idea is a storage array would have something called a storage provider, and it would present capabilities of the storage up to the vSphere layer. This information could be used to create profile-driven storage. For example, this might help identify different types of storage based on performance, protection types, or other features. This would then assist the admin to help make the right storage selection based on his or her requirements. I would also say that this is becoming a basic feature that if you don’t offer it… well, it would not be a deal breaker, but I would question why you don’t.
Storage Replication Adapter (SRA): An SRA is used when deploying Site Recovery Manager (SRM) from VMware. SRM is a tool to allow for automated failover of replicated VMs to your recovery site. The SRA is the adapter that sits between SRM and your storage-replication method. If you are a storage vendor and you offer a replication method than you must offer an SRA. This will allow your customers to utilize SRM for their DR methods. At the moment, pretty much every major enterprise storage vendor offers SRAs for its products. I’m happy to report that more of the Flash/hybrid storage vendors are quickly releasing SRAs for their products. This will help adoption of their offerings by customers that require SRM in their plans.
Plugins: So far, a plugin offering from storage vendors have meant vCenter plugins that install into the classic vSphere client. These typically offer a limited number of functions that allow you to do some basic storage provisioning, find out details about underlying storage for a datastore, and perhaps show you additional performance details. So far there are a few vendors that offer what I would call a real plugin and not just a webpage that is inserted into vCenter. I hope to see vendors offering plugins for the vSphere Web Client in the near future, since this is future method for managing VMware.
vC OPs adapter: vCenter Operations Manager (vC OPs) is the popular VMware performance management and monitoring product. Some storage vendors have already released adapters that allow their storage products to publish performance data into vC OPs. This allows you to get all of your data in a single tool. This is a win for most IT shops.
VM aware: This is something that came to market a couple of years ago when Tintri released their storage offering. Prior to Tintri, storage was dumb and all it understood was LUNs and had no idea what a VM was. Well, since Tintri came to market (and others are working towards this), storage is now starting to understand what VMs are. This makes the life of a VMware admin much easier, they can now easily connect VMs to the underlying storage and understand capacity and performance more intimately. Also, tools that replicate VMs and provide other functions can begin to work on a per-VM basis rather than on the datastore level.
PowerShell support: Does the storage vendor publish a set of PowerShell cmdlets that allow you to configure or manage the storage array? This is beneficial for initial setup, configuration changes, or as a method to allow for ongoing automation.
Orchestrator plugin: VMware Orchestrator is the workflow engine to create workflows for automation and orchestration. There are software and hardware vendors adopting this path of creating plugins to allow for Orchestrator to connect and automate their products.
Automation API: If there is not an Orchestrator plugin or PowerShell option, then an open API would be the other option. Does the storage vendor offer a REST API or another API as a way of automating the storage?
Multipath options: There are a limited number of storage vendors that offer their own multipathing policies. Beyond whether they offer their own, I think that it is important to research and find out if they support different methods that are included with vSphere such as Round Robin.
I hope that this has helped clarify what storage vendors can offer in the way of VMware integrations. These are some important things to consider when evaluating storage for VMware in your environment.