PowerCLI script to check/configure Datera Best Practices on ESXi hosts

Preparation 1 - Install Powershell on the node you want to run the script
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	MacOS:
		1.  brew cask install powershell
		2.  Verify if PowerShell 6.2.2 installed by "pwsh" command
	Ubuntu (16.04):
		1. Download powershell_6.2.2-1.ubuntu.16.04_amd64.deb   
		2. Use "sudo apt-get install <package>" command to install PowerShell 6.2.2
	Windows (Windows 2012 R2)
		Powershell installed by default

Preparation 2 - Install VMware PowerCLI on the node you want to run the script
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	MacOS:  
        Ubuntu: 
		1.  Go to powershell console by command "pwsh"	
		2.  Run the command "Install-Module -Name VMware.PowerCLI"
	Windows:
		1.  Download VMware-PowerCLI-6.5.0-4624819.exe from VMware
		2.  Install VMware-PowerCLI-6.5.0 by clicking the executable 

Features
--------
	Powercli script Datera_VMWare_setup.ps1 is a tool to display and 
        configure 4 storage or iSCSI parameters on ESXi hosts via vCenter based on 
        Datera VMware best practice.

	### 4 parameters ###
     	- ATS heartbeat                     -- Disabled
     	- iSCSI QD                          -- 16
     	- DelayedACK of SW iSCSI adapter    -- Disabled
     	- DATERA NMP SATP rule              -- Round Robin and IOPS=1 for Datera storage

        ### How to run ###
        1.   Download the script Datera_VMWare_setup.ps1 from github into your current directory
        2.   Start Powershell console 
        3.   Connect to vCenter from powercli console either on Windows, or MacOS, or Ubuntu
             Windows: 
	     	PowerCLI C:\> Connect-VIServer -Server <vCenter server IP or FQDN> -Force
	     MacOS or Ubuntu:
             	PS /home/ghg> Connect-VIServer -Server <vCenter server IP or FQDN> -Force
	     (the -Force parameter is only required if VCSA does not have proper SSL certificates) 
        4.   Display 4 parameters on all ESXi hosts managed by vCenter   
	     Windows:
              	PowerCLI C:<path_to_the_script>\Datera_VMWare_setup.ps1
	     MacOS or Ubuntu:
		PS /home/ghg> ./Datera_VMWare_setup.ps1

        5.   Update 4 parameters on all ESXi hosts that iSCSI targets are not connected.   
	     Windows:
              	PowerCLI C:<path_to_the_script>\Datera_VMWare_setup.ps1 -Update yes 
	     MacOS or Ubuntu:
		PS /home/ghg> ./Datera_VMWare_setup.ps1 -Update yes
        
	### Tested environments ###
	We did test the script in the following environments:
	    1)  ESXi 6.0u3 and vCenter 6.0 u3h
	    2)  ESXi 6.5u2 and vCenter 6.5 u2d   		
	    3)  ESXi 6.7u2 and vCenter 6.7 u2c	

FAQ
---

Q: Why do we need to setup these parameters?
A: The details can be found in the comments in the source of Datera_VMWare_setup.ps1  

Q: What is the output of 4 parameters?	
A:
==== ATS hearbeat on <ESXi node FQDN> (1:enabled 0:disabled)  ====

Uid         : /VIServer=vsphere.local\administrator@<vCenter FQDN>:443/VMHost=HostSystem-host-395/AdvancedSetting=VMHostSetting-VMFS3.UseATSForHBOnVMFS5/
Value       : 0
Description :
Type        : VMHost
Entity      : <ESXi node FQDN>
Id          : VMHostSetting-VMFS3.UseATSForHBOnVMFS5
Name        : VMFS3.UseATSForHBOnVMFS5
Client      : VMware.VimAutomation.ViCore.Impl.V1.VimClient

==== iSCSI Queue depth on <ESXi node FQDN> ====

Description : Maximum Outstanding Commands Per LUN
Name        : iscsivmk_LunQDepth
Type        : int
Value       : 16

==== Delayed ACK of software iSCSI adapter on <ESXi node FQDN> ====

ID      : vmhba64
Current : false

==== NMP SATP RULE of DATERA on <ESXi node FQDN> ====

ClaimOptions :
DefaultPSP   : VMW_PSP_RR
Description  : DATERA custom SATP Rule
Device       :
Driver       :
Model        :
Name         : VMW_SATP_ALUA
Options      :
PSPOptions   : iops=1
RuleGroup    : user
Transport    :
Vendor       : DATERA

Q: Why is the script skipping some of my ESXi hosts?
A: The script will purposefully skip ESXi host(s) that have iSCSI targets configured,
   to avoid damaging your ESXi server configuration. This script is intended to be run
   when a new ESXi host is added to vCenter Server.