Data Center

Getting Storage Right for Business Critical Applications on VMware

by Marcus Thordal ‎04-14-2017 11:28 AM - edited ‎04-14-2017 11:31 AM (3,386 Views)

 

With more than 75% of all workloads in the enterprise data center virtualized predominantly on VMware (according to Gartner) combined with the power of flash storage technologies; getting storage right for Business Critical Applications on VMware is more important than ever.

 

                                                 Business Critical Applications

                                          Business Critical Applications dependency on Performance and Availability

 

The core requirements for BCA are always focused on performance, being highly available and agile to meet scaling needs in alignment with the business without impact on performance or availability. In addition their data must be protected and recoverable with small (or no) margin for data loss and downtime in the event of a disaster.

These application requirements reflecting the importance to the business directly translate to the requirements for the infrastructure to host the application.

 

Business Critical Applications on VMware

Many VMware architects will tell you that getting storage performance right is commonly the largest challenge especially because if you don’t get it right in the design phase it can be extremely hard to solve once critical applications are in production, the business depends on the availability and performance while the data starts to grow.

When designing a vSphere infrastructure shared storage is necessary to take full advantage of server virtualization.

The shared storage can be based on a distributed storage model like VSAN, IP accessed array (NFS/iSCSI) or Fibre Channel array.

 

The Network Matters for Storage Performance and Availability

From the network perspective, the needs of Storage and Application services are quite different, and may conflict with each other.  Having a separate storage network will address this issue.  From a storage network perspective, the main difference between the storage types is that Fibre Channel connected storage is delivered with two redundant networks transporting only storage traffic (commonly) on a simplistic core-edge network that only transports storage traffic at low latency by traversing a total of 4 switches (two in each direction).

 

                                                                GSRBCA-1-Img2-SANTopology.png

                                                                           Fibre Channel SAN Topology Design

 

For both distributed storage arrays and IP accessed arrays the storage network is shared on the same single physical network as the application. Commonly the network topology is a spine leaf architecture which contributes to IO response time for writes equal to the latency of traversing six switches (three in each direction) while competing for network resources with the applications.

 

                                           GSRBCA-1-Img2-NetworkTopology.png

                                                                         Data Center Network Topology Design

 

The storage connectivity model which aligns best with the core requirements for BCA is Fibre Channel with the highest performance, availability, agility and serviceability combined with the instrumentation for monitoring and the support for NVMe which will make flash even faster. Read more about the importance of visibility into storage traffic on your network as your requirements to performance and high availability increase, in this great blog by AJ Casamento.

 

In the continuance of this blog I will start by going through best practice SAN configuration on vSphere to get the storage right for your business critical applications.

 

                                                                     Network&SAN

                                                     Reference Design for Business crital Applications on VMware