RE-IP to VCD fails when failing over VPG with re-IP settings and Guest customization checked in the ZVM GUI 

KB Number:
000001492

Symptoms:
When-failing-over-PVG-s-to-VCD-RE-IP-might-fail-on-changing-NIC-settings.
Re-IP doesn't work properly when failing over VPG with re-IP settings and Guest customization checked in the ZVM GUI 
 

Cause:
The current flow in ZVM is that we try to power on the guest OS to identify if VMTools is installed on the VM for enabling guest customization. 
Once VMTools was identified we are powering off the VM and the NIC is not fully loaded to the VM and the power off leaves the VM in a corrupted state which leads to this issue.
 

Solution:

The solution for this scenario is to delaying the VMTools service start time
there are 3 ways to implement it:

1. Increase the RAM value for the problematic VM from 4 to 8. 

OR 

2. Set a tweak on the cloud ZVM: 
t_ZvmVCDSleepTimeWaitingForToolsToInitializeInMS = 30 
This tweak sets the time to wait between checks for the VMTools (default is 10 seconds) - can be changed to 30 seconds 

a. Log into the DR site ZVM and browse to C:\Program Files (x86)\Zerto\Zerto Virtual Replication 
b. Open the tweaks.txt file 
c. Within the tweaks.txt file add the following line: 
t_ZvmVCDSleepTimeWaitingForToolsToInitializeInMS = 30 
d. Save tweaks.txt file 
e. Reboot ZVM service 

Please note the tweak is case sensitive. 

OR 

3. Set a startup delay for the VMTools on the protected VM: 
Delaying the VMTools service start time should do the work. 
There are two methods of doing that, both require registry changes (at the protected VM), so registry backup is recommended first: 

a. Setting a dependency of VMTools service on other networking functionality services such as DHCP, NetLogon - 
this can be done by adding to a new [bold]REG_MULTI_SZ[bold] key to registry path HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\VMTools 
the values should be the services names, deferred by lines. 

Here's a Microsoft KB with instructions: 

https://support.microsoft.com/en-us/help/193888/how-to-delay-loading-of-specific-services 
You can add the key manually or paste the following lines on a new ".reg" file on the VM (using notepad): 

Windows Registry Editor Version 5.00 

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\VMTools] 

"DependOnService"=hex(7):44,00,48,00,43,00,50,00,00,00,4e,00,65,00,74,00,4c,00,\ 
6f,00,67,00,6f,00,6e,00,00,00,00,00 

b. Setting a timed delay for the VMTools service. 
This can be achieved by setting the VMTools properties from the services panel - under "Startup type" choose "Automatic (Delayed Start)". 
It can also be achieved with registry editing, to registry path HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\VMTools 
two values: 
REG_DWORD named DelayedAutostart = 1 
REG_DWORD named AutoStartDelay = (delay time in milliseconds) 

Here's a *.reg file that adds 30 seconds delay: 

Windows Registry Editor Version 5.00 

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\VMTools] 

"DelayedAutostart"=dword:00000001 
"AutoStartDelay"=dword:00007530 

####### 
 


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