As they consider a potential transition to a hyperconverged architecture (HCI), organizations need to decide how to migrate data to the HCI platform. They also need to decide what to do with their legacy storage infrastructure that still will be usable for years. The problem is that most HCI vendors provide no transition plan for organizations looking to make that move. Instead, they expect the customer to “sweep the floor” in terms of their existing storage investment.
One solution to these problems is to make sure the same storage software is running on both the legacy storage systems and the HCI solution. Using a storage-management software layer across the two environments means that data between each environment can replicate directly between the old and the new storage. It also means that once the replication is complete, IT can repurpose the old storage system as a replication target or as archive storage.
Software-Defined Storage for HCI
A vital element of any HCI solution is storage software. In fact, most environments want to continue using the same hypervisors and network software, which leaves storage as the differentiating capability for these platforms. The challenge is that the HCI storage software optimization is only for that HCI use case. Most vendors do not enable it to run independently on hardware acting as a dedicated storage solution. Software-Defined Storage (SDS) on the other hand, is designed to run on a dedicated server and control multiple storage systems. If the SDS vendor also optimizes their software to run in a virtualized environment, they can deliver similar functionality as a traditional HCI solution, but with some added benefits.
The Benefits of SDS for HCI
The first key benefit of SDS for HCI is that it can easily migrate data from legacy primary storage systems to the HCI environment. The SDS for HCI software makes for smooth migration because the HCI cluster is now running the same software as the legacy primary storage system. The SDS for HCI software easily replicates volumes between the two systems. Additionally, that replication is transparent to users, so the cutover to the new HCI environment is seamless.
A second benefit is that IT professionals are using the same software to manage and trigger storage features like snapshots, replication, and tiering – even data services like encryption. Using the same software eliminates the need for having to learn two storage software applications or dedicating different personnel to manage each environment. A single, small storage team can control both the original virtualization cluster and the new HCI environment with the same commands and features. Using the same software also means there is less pressure on IT to switch everything over to the new environment. They can keep some systems running on the original virtualization cluster and others running on the new HCI cluster.
The third benefit of SDS for HCI is that IT can repurpose the legacy storage infrastructure, which typically still has years of serviceable life left in it, for use as a replication target. That way, in the event of a failure in the HCI cluster, the storage software can migrate critical VMs back to the legacy cluster. Performance should be more than adequate considering that these systems were the production environment prior to the HCI conversion.
As the original primary storage system ages, and as IT becomes comfortable with the new HCI architecture design, the organization may not want to use this storage even as a replication target for DR. A fourth benefit of using the same SDS solution on both the original virtualization cluster and the new HCI cluster is repurposing the original storage infrastructure for backup or archive storage instead.
Using the original storage infrastructure for backup or archive storage may be a suitable alternative and enable the organization to get significantly more life out of the investment. Repurposing the original SAN for backup or archive can reduce future investments in backup storage. It also lowers the rate at which IT needs to add additional storage capacity to the HCI cluster.
A final of advantage of using SDS in the HCI environment is its ability to leverage the cloud. While some HCI clusters can replicate data to the cloud as a DR copy, they can’t do much more than that. SDS for HCI should have the ability to run as an instance in the cloud. With the same storage software now running in the cloud, organizations can replicate data to the cloud, and they can run instances of their applications in the cloud without modification. Running the same SDS instance in the cloud means the organization can leverage the cloud for not only DR, but also peak workload bursting and Test/Dev.
Most organizations considering HCI also have a SAN in place. Entirely replacing that SAN with the new HCI environment, doesn’t make sense for HCI customers. The challenge is they have limited options available to them if they want to support both. Taking a more software-defined storage approach to both SAN and HCI may give customers a seamless way to move data between the two environments.
To learn more, watch our Lightboard Video, “How to Move to HCI While Retaining the Best of SANs“, as we chalktalk through the potentials of using the same storage software on both the dedicated SAN environment and in the HCI environment.