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Affected Versions
Source Hypervisor
Target Hypervisor

Problem: Failover to vCD is stuck in “promoting” state due to MAC address conflict

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Root Cause

The MAC address of the recovery VM is conflicted with the MAC addresses used by another VM or the reserved MAC addresses in vCenter of the recovery site.

For more information, please refer to the following VMware KB:


  • The failover live or failover test is stuck in 30-40% progress
  • In the vCD of the recovery site, the VMs within a vApp will not power on and vCD will prompt the user with a generic error.
  • In vCenter attempts to power the virtual machine on fail with a status message that the MAC address is in conflict:
00:0c:29:XX:YY:ZZ is not an allowed static Ethernet address. It conflicts with VMware reserved MACs.
00:50:56:XX:YY:ZZ is not a valid static Ethernet address. It conflicts with VMware reserved MACs for other usages.


  1. Try to power on all VMs within the failed-over vApp;
  2. In vCD, reset the MAC Address for the VMs which are not powering on using the following VMware KBs:
  1. Power on the machines. The failover process will continue.