Dell EMC’s PowerPath: Worth a second look.

Tom Marcoulier

by Tom Marcoulier

Let’s start off with a quick refresher – what is PowerPath?

PowerPath is a host-based software for automated data path management, failover and recovery, and optimized load balancing.

Key features:

  • Provides intelligent multipathing in VMware vSphere and Microsoft Hyper-V environments
  • Optimized for EMC VMAXVNXVNXeUnity, and XtremIOstorage arrays
  • Supports qualified non-EMC arrays
  • Works with Fibre Channel, iSCSI, and Fibre Channel over Ethernet (FCoE)
  • Dynamically load balances across all available I/O paths for best virtual machine performance
  • Increases scalability by intelligently managing data path usage
  • Improves application availability: automatically detects data path failures, fails over to alternate paths, and restores paths after failures are resolved

Coupled with PowerPath Viewer, system administrators have one place to view path managements across their entire server infrastructure.

During my career, I have found that there are products that are a must haves for every IT department. If your IT department has VMware, one of those products is PowerPath Virtual Edition aka PowerPath/VE.

VMware’s ESX 4.x release introduced an enhancement to storage connectivity. The vStorage APIs for multi-pathing provided a framework that enables storage vendors to develop multi-pathing ‘Extension Modules’ that plug into vSphere. These plug-in modules provide multi-pathing software that can be used in place of vSphere’s native multi-pathing functionality. PowerPath/VE installs as a kernel module on the vSphere host.

Why does this matter? Hyper-consolidation of virtual servers in the hundreds, and at some extreme thousands, will create a large number of I/O requests all competing for the same data paths. This resource contention can be amplified by increasing the number of virtualized applications and to some degree VM mobility. In addition to these challenges, everyday data path issues can occur regardless of server virtualization, such as faulty paths (think human error) and HBA firmware errors. As more production applications become virtualized, the performance and availability impacts of resources become even more spotlighted.

This is where VMWare’s native multi-pathing (NMP) hits its limit and PowerPath/VE takes over.   PowerPath/VE, with intelligent, automated load balancing, will outperform VMware native multi-pathing set to the round robin policy for IOPS and throughput intensive workloads resulting in less SAN congestion.  (

If you have not yet tried or it has been a while since you used it, I suggest that you install a trial version of PowerPath/VE.