IP customization failing after Bulk Migration with the error "Can't get adapter name for MAC ##:##:##:##:##:##"

Products

• VMware HCX

Issue/Introduction

• The following error is observed in the Windows VM path C:\Windows\Temp\vmware-imc\guestcust.log:

  [2025-10-07T10:03:36:                 AdapterConfig:  DEBUG] Getting adapter name corresponding to the MAC address '00:##:##:##:##:92'
  [2025-10-07T10:03:36:                 AdapterConfig:   WARN] Can't get adapter name for MAC '00:##:##:##:##:92'
  [2025-10-07T10:03:36:                 AdapterConfig:  DEBUG] Adapter name: ''
  [2025-10-07T10:03:36: ExtendedWinCustomizationLogic:  DEBUG] All NICs are not ready yet. Will try again after 10000 milliseconds

 

• The guest customization payload found in HCX Manager /common/logs/web.log lists the MAC address assigned to the virtual machine at the vSphere level:

                  networkCustomizations: [class GuestCustomizationNetworkCustomizations {
                      macAddress: 00:##:##:##:##:92
                      ipAddress: 10.###.###.10
                      netmask: 255.255.255.0
                      gateways: [10.###.###.1]
                      dns: []
                      dnsSuffix: []
                  }]

 

• The virtual machine guest OS lists through "ipconfig /all" a different MAC address for the same network device:

   Connection-specific DNS Suffix  . :
   Description . . . . . . . . . . . : vmxnet3 Ethernet Adapter
   Physical Address. . . . . . . . . : 00-##-##-##-##-AF
   DHCP Enabled. . . . . . . . . . . : No
   Autoconfiguration Enabled . . . . : Yes
   IPv6 Address. . . . . . . . . . . : ####:##:#:##::####:#####(Preferred)
   Link-local IPv6 Address . . . . . : ####:##:#:##::####:#####(Preferred)
   IPv4 Address. . . . . . . . . . . : 10.###.###.10(Preferred)
   Subnet Mask . . . . . . . . . . . : 255.255.255.0
   Default Gateway . . . . . . . . . : 10.###.###.1

Cause

The Guest OS Customization process cannot identify the network adapter in the destination virtual machine that matches the MAC address specified in the "networkCustomizations" specification. A mismatch between the MAC address at the vSphere level and the Guest OS level can lead to issues in the Guest OS customization process to fail.

Resolution

Check the MAC address in both the Guest OS and vSphere to ensure they match prior to proceeding with the migration.

To manually configure the MAC address of a virtual machine on the vSphere side, please refer to Changing the MAC address of a hosted virtual machine