Home > Storage > PowerMax and VMAX > Storage Admin > Dell PowerMax and VMware vSphere Configuration Guide > PowerPath/VE Multipathing Plug-in and management
There is neither a local nor remote GUI for PowerPath on ESXi so administrators should use the rpowermt utility. If using the PowerPath Management Appliance, however, it is possible to monitor the ESXi hosts paths. This is shown in Figure 51. Note the red box is showing the FC-NVMe devices and how PP/VE has recognized them as ALUA.
Figure 51 PowerPath Management Appliance
When the ESXi host is connected to a PowerMax array, the PowerPath/VE kernel module running on the vSphere host will associate all paths to each device presented from the array and associate a pseudo device name. An example of this is shown in Figure 52, which has the output of rpowermt display host=x.x.x.x dev=emcpower20. Note in the output that the device has four paths and displays the recommended, and default, optimization mode (SymmOpt = Symmetrix optimization).
Figure 52 Output of the rpowermt display command on a PowerMax device
For more information on the rpowermt commands and output, consult the PowerPath/VE for VMware vSphere Installation and Administration Guide.
As more PowerMax directors become available, the connectivity can be scaled as needed. PowerPath/VE supports up to 32 paths to a device.[6] These methodologies for connectivity ensure all front-end directors and processors are utilized, providing maximum potential performance and load balancing for vSphere hosts connected to the PowerMax storage arrays in combination with PowerPath/VE.
VMware ESXi uses modified QLogic and Emulex drivers that support multiple targets on every initiator. This functionality can be used to provide greater resiliency in a VMware ESXi environment by reducing the impact of storage port failures. Furthermore, presenting a device on multiple paths allows for better load balancing and reduced sensitivity to storage port queuing. This is extremely important in environments that share Dell PowerMax storage array ports between VMware ESXi hosts and other operating systems.
Figure 53 shows how to implement multiple-target zoning in a VMware ESXi environment. The VMware ESXi has two HBAs, vmhba2 and vmhba64; however, the device can be accessed from four different paths with the following runtime names: vmhba64:C0:T5:L6, vmhba2:C0:T2:L6, vmhba64:C0:T2:L6 and vmhba2:C0:T5:L6. This is achieved by zoning each HBA in the VMware ESXi to two Dell PowerMax storage array ports.
The VMkernel assigns a unique SCSI target number to each storage array port. In Figure 53, the VMkernel has assigned SCSI target numbers 2 and 5 to each Dell PowerMax storage array port into which vmhba1 logs in, and also 2 and 5 to each Dell PowerMax storage array port into which vmhba5 logs in.
Note: Dell does not require that each ESXi host have the same SCSI target number for each device. As previously noted, however, there are some business cases where Consistent LUN is required. In those environments device from PowerMax can be presented with the consistent LUN attribute.
Note: This section does not discuss how multiple target zoning can be implemented in the fabric. Dell always recommends one initiator and one target in each zone. Multiple target zoning discussed in this section can be implemented as a collection of zones in which each zone contains the same initiator but different targets.
Figure 53 Increasing resiliency of ESXi host to SAN failures
[1] Dell does not support using the MRU PSP for NMP with PowerMax.
[2] Except NVMeoF devices.
[3] The Mobility ID (MID) is a format of device identifier that provides a universally unique volume identifier.
[4] If running an SRDF/Metro vMSC uniform (cross-connect) configuration with RR PSP and the arrays are not co-located (datacenter or campus), the IOPS should be adjusted higher than 1. The default value of 1000 is acceptable, though testing should be conducted as the IOPS may require lowering to increase performance.
[5] There is a limited CLI available on ESXi if Tech Support mode is enabled.
[6] ESXi supports 2048 total combined logical paths to all devices in vSphere6.5 and 4096 in 6.7 and higher.