All-flash solutions come in different packaging, depending on your specific use case. The two most popular deployments are AFA SAN appliances and AFA hyperconverged appliances. Each solution provides its own set of pros and cons, which we will discuss briefly in a moment.
The other two popular deployments are the x86 server-side internal all-flash drives and the software-defined storage AFA solutions. Both of these options provide unique value, while the SDS option provides the most value out of the four AFA deployment options.
Let’s review them one-by-one:
AFA SAN Appliance
All-flash SAN appliances are manufactured by both mature companies such as HP, IBM, Dell/EMC, NetApp, Hitachi and also newcomers like Pure Storage, Tegile, Nimble, Tintri, Kaminario, NexGen, and SolidFire. However, several of these newcomers have been bought out by the big names, and new AFA startups are rising to make the all-flash market extremely competitive.
From a capacity perspective, choosing an AFA model from any of these manufacturers totally depends on how many terabytes of data your organization is using. These all-flash SAN appliances are used as building blocks—you can start with one block and scale out by adding more blocks as your data footprint grows. This approach is easy to adapt, but you will eventually end up falling in the “vendor lock-in” trap. This means that you have very little control during price negotiations for renewals or expansion.
Keep in mind that each manufacturer has various models that provide specific amounts of storage capacity. Consider the X10 model from Pure Storage, which provides 55TB of capacity. If you have a large 250TB environment, you will simply buy 5 of the X10 AFA SAN appliances, and you are all set. Or you can go with the X20 model, which provides 275TB’s of space. It’s that simple.
While performance is the #1 benefit that all-flash arrays provide, other enterprise-level functionalities may not be available, such as high-availability, replication, metro-clusters, cloud integration, etc. In addition, you will have another GUI to learn and manage, requiring training and maybe even certifying your IT staff. Again, the features and requirements vary on a case-by-case basis. You will need to do your homework before committing solely on performance metrics.
Gartner’s latest Magic Quadrant for Solid-State Arrays (SSA/AFA) will help you learn more about this group of all-flash SAN manufacturers.
AFA HCI Appliance
The most popular names you will hear in this space are Nutanix, HPE Simplivity, Pivot3, Dell/EMC VxRack, NetApp HCI, and Cisco HyperFlex. These are turnkey solutions you can stack as blocks and scale out as you grow. You need to pay premium prices for the convenience and performance benefits. If your company has the deep pockets to go all the way, then the possibilities are endless.
A few of the top benefits with all-flash hyperconverged solutions are deduplication and compression. These features can help alleviate the high costs incurred with investing in all-flash. Deduplication and compression ratios can range as low as 1.5-to-1 and as high as 5-to-1—or even 8-to-1 in rare cases. Your data efficiency rates totally depend on the type of data you are storing and the block size of this data. The higher the I/O block sizes, the lesser the ratios will be.
Another concern to consider is understanding which hypervisors are supported by each of the AFA HCI appliances. If you ever need to switch hypervisors, such as migrating from ESXi to Hyper-V, you will probably need to buy a new HCI appliance that supports your new virtual environment. That is a tough financial hit to take if your AFA HCI appliance does not support multiple hypervisors.
This option can help boost performance for isolated applications that require higher IOPS than what your SAN can offer. This approach is both cheap and practical. There is no need to make huge investments on appliances. Simply buy the latest SSD drives supported by your server vendor, add them to any available drive bays, pair them up with a fast controller, and you are done. That was too easy.
But there is a catch: you can’t share these fast SSD drives with the rest of your tier-1 applications running in other servers. The other issue here is the lack of native migration options from the internal flash arrays to any external all-flash appliance if you eventually decide to upgrade to the all-flash SAN model. Although this option is cost effective, it is a temporary workaround and not a long-term scalable solution.
AFA SDS Appliance
Now that you understand the pros and cons of the previous deployment options, let’s review the advantages available with software-defined storage all-flash arrays. Software-defined storage delivers all the benefits the all-flash appliances provide but without the drawbacks. Instead, you actually gain greater flexibility and freedom to choose, which is also known as all-flash converged servers.
In addition, you get to choose any x86 server and add as many SSD drives as you need. You can even add PCIe Flash cards to add more acceleration. Let’s say, for example, you choose the latest SuperMicro server with two 24 port NVMe backplanes, each supporting up to 24x 2.5″ NVMe SSDs. You can add 48x 3.84TB SSDs, which adds up to 184TB of raw flash storage on a 2U server. That is maximum efficiency at every level. Less rack space required for 100+ TB of flash, lower cost than comparable AFA SAN appliances, and the highest performance and best enterprise features available through software-defined storage.