Agustín Malanco’s Blog: vSAN and Native AWS Storage Services in VMC
In our previous article, we introduced the series of articles on VMware Cloud on AWS (VMC) and discussed the architecture of vSAN, a critical component of the SDDC (Software-Defined Data Center) solution. Today, we will delve deeper into the topic of storage in VMC, discussing vSAN and native AWS storage services, and how they can be integrated with VMC.
vSAN: A Key Component of SDDC
As we mentioned earlier, vSAN is a critical component of the SDDC solution, providing a software-defined storage layer that pools local disk resources from participating servers to create a shared, centralized storage pool. In an VMC environment, vSAN is used to provide storage for virtual machines (VMs), and it can be configured in different ways depending on the hardware profile of the servers being used.
For example, in the case of an i3 server profile, each server has 8 storage devices (NVMe drives), as shown in the following configuration:
[INST01] -> 8x NVMe drives
With this configuration, we can achieve the following benefits:
* All NVMe drives are assigned to vSAN, while a separate Elastic Block Store (EBS) volume is allocated for boot purposes.
* Elastic vSAN provides flexibility in terms of capacity requirements for instances of type R5.
Elastic vSAN: A New Capacity Option for R5 Instances
In addition to the standard vSAN configuration, VMC also offers a new capacity option called Elastic vSAN, which is specifically designed for instances of type R5 (Bare Metal on AWS). In this case, the physical servers are considered “diskless,” with only a single EBS volume for boot purposes and no local disks. The storage requirements for these instances are fulfilled by adding additional EBS volumes as needed:
[INST01] -> 1x EBS (boot) + N x EBS (storage)
The Elastic vSAN feature allows you to dynamically add or remove EBS volumes as needed, providing a flexible and scalable storage solution for R5 instances. This feature is particularly useful for workloads that require a high degree of flexibility in terms of storage capacity.
Comparison of i3 and R5 Instances
When selecting between i3 and R5 instances, it’s important to consider the following factors:
| Criteria | i3 Instances | R5 Instances |
| — | — | — |
| Local Storage | 8x NVMe drives | No local storage (diskless) |
| Boot Volume | Separate EBS volume | Single EBS volume for boot |
| Capacity | Up to 35TiB (adjustable in 5TiB increments) | 15-35TiB (adjustable in 5TiB increments) |
| Compression, Encryption, and Deduplication | Supported | Supported |
Based on these factors, you can choose the appropriate instance type based on your specific requirements. For example, if you need a high degree of local storage capacity and support for compression, encryption, and deduplication, an i3 instance may be the better choice. However, if you require a more flexible and scalable storage solution with a lower upfront cost, an R5 instance may be more suitable.
Conclusion
In conclusion, vSAN and native AWS storage services are two critical components of the SDDC solution in VMC. By understanding how these components work together, you can select the appropriate instance type based on your specific requirements and create a highly available, scalable, and secure storage environment for your virtual machines. Stay tuned for our next article, where we will delve deeper into technical topics such as storage performance, availability, and resilience in VMC.