Unexpected exception from VM protection prepare phase

Products

• VMware Live Recovery

Issue/Introduction

1. You cannot protect a VM in VLSR (SRM). 

ERROR
Operation Failed
Internal error: Received unexpected exception during prepare phase. Internal error: Unexpected exception from VM protection prepare phase.
Operation ID: 7eecbc02-####-####-####-9829b0d54bb2
4/10/25, 11:45:19 AM -0500

2. VM protection status shows not configured in protection groups. 



3. Virtual machine monitor tab, task view displays this error. 




VMware-dr.log:

2025-04-16T14:58:33.449Z error vmware-dr[379547] [SRM@6876 sub=Replication opID=3c800cb3] Unexpected exception from VM protection  prepare phase: (vim.fault.InsufficientPerCpuCapacity) {
-->    faultCause = (vmodl.MethodFault) null, 
-->    faultMessage = (vmodl.LocalizableMessage) [
-->       (vmodl.LocalizableMessage) {
-->          key = "com.vmware.drs.constraints.cpu.InsufficientPerCpuCapacity", 
-->          arg = (vmodl.KeyAnyValue) [
-->             (vmodl.KeyAnyValue) {
-->                key = "requestedPerCpu", 
-->                value = 2500
-->             }, 
-->             (vmodl.KeyAnyValue) {
-->                key = "maxPerCpu", 
-->                value = 2494
-->             }, 
-->             (vmodl.KeyAnyValue) {
-->                key = "host", 
-->                value = "host-####"
-->             }
-->          ], 
-->          message = "The host host-#### can not satisfy requested 2500 Mhz per vCPU for this VM. Maximum core frequency is 2494 Mhz per physical CPU."
-->       }
-->    ], 
-->    host = 'vim.HostSystem:ef745592-####-####-####-8569688a4642:host-####'
-->    msg = "Insufficient capacity on each physical CPU."
--> }
-->

 

2025-04-08T14:32:23.271-05:00 info vmware-dr[338557] [SRM@6876 sub=DrTask ctxID=5ae83d74 opID=d646e971-####-####-####-ffdb1bac7fdd-protectVms:9abc:ac19-startRemoteOperation:dfeb] Task 'dr.multiSiteOperation.MultiSiteOperationManager.startRemoteOperation1727' failed
--> (dr.multiSiteOperation.fault.CohortPrepareFault) {
-->    faultCause = (vmodl.MethodFault) null,
-->    faultMessage = <unset>,
-->    siteFault = (dr.multiSiteOperation.fault.MultiSiteFault.SiteFault) [
-->       (dr.multiSiteOperation.fault.MultiSiteFault.SiteFault) {
-->          siteUuid = "a5365b5b-4cec-4611-ad43-e047335bda75",
-->          fault = (dr.fault.InternalError) {
-->             faultCause = (vmodl.MethodFault) null,
-->             faultMessage = <unset>,
-->             reason = "Unexpected exception from VM protection prepare phase"
-->             msg = "Internal error: Unexpected exception from VM protection prepare phase."
-->          }
-->       }
-->    ]
-->    msg = ""
--> }

Environment

VMware Live Site Recovery 9.x

Cause

This error arises when the reservation of a VM exceeds the physical CPU processor speed. 

Resolution

Follow the guidelines mentioned below to fix this error. 

Quoting from the log message - The host host-#### can not satisfy requested 2500 Mhz per vCPU for this VM. Maximum core frequency is 2494 Mhz per physical CPU.

Number of vCPU = 4
Reservation (MHz) = 10000
Processor (CPU) Speed (GHz) = 2.49

You can get the precise processor speed by navigating to the host and clicking on configure option. 

NOTE: Apply this formula to determine the exact reservation you can assign to your Virtual Machines. 

Processor (CPU) Speed (MHz) * Number of vCPU = Reservation (MHz) 

2490 * 4 = 9960 

The Edit Settings screenshot above clearly shows that this VM's reservation size exceeds the hardware processor speed threshold.

To avoid this error, the VM reservation size must be set to 9960 or lower.