Protecting machines agentlessly through a Hyper-V Cluster fails with "Cannot resolve agent host name" (4039883)

When adding machines to agentless protection through a Hyper-V Cluster's Virtual Machines page, protection fails with "Cannot resolve agent host name." This issue happens given a specific scenario:

1. You have successfully protected machine(s) agentlessly through a Hyper-V Cluster.
2. Adding additional machine(s) to agentless protection through the Hyper-V Cluster's Virtual Machines page fails.

Protection of additional machines through the Virtual Machines page will fail with the following errors:

Stack Trace:

Server side:

• The remote machine is blocked by the firewall.
• The host name or IP address is wrong or the remote machine is shut down
• The "Remote Procedure Call (RPC)" service is not running on the remote machine. WMI query: Select Name, DNSHostName From Win32_ComputerSystem -namespace root\cimv2 ---> Replay.Common.Contracts.WmiApi.WmiException: Cannot connect to a remote machine 'redcluster'Cannot connect to a remote machine '{0}' This error could be caused by one of the following:
• The remote machine is blocked by the firewall.
• The host name or IP address is wrong or the remote machine is shut down
• The "Remote Procedure Call (RPC)" service is not running on the remote machine. ---> System.Runtime.InteropServices.COMException: The RPC server is unavailable. (Exception from HRESULT: 0x800706BA) at System.Runtime.InteropServices.Marshal.ThrowExceptionForHRInternal(Int32 errorCode, IntPtr errorInfo) at System.Management.ManagementScope.InitializeGuts(Object o) at System.Management.ManagementScope.Initialize() at Replay.Common.Implementation.WmiApi.Wmi.Connect()

Work around:

1. On your Core, open the Network and Sharing Center and click on Change adapter settings.
2. Right click on your network adapter and click Properties.
3. On the Networking tab double click Internet Protocol Version 4 (TCP/IPv4).
4. At the bottom of the General tab click Advanced.
5. Select the DNS tab and click Add.
6. Add the Cluster Domain Controller IP and click the up arrow so it is at the top.
   
   
   
7. Select Append these DNS suffixes (in order):, click Add, and enter the Domain Controller Forest Name to DNS suffixes.
   
   
   
8. Click OK to finish.
   NOTE: You may need to restart the network adapter (disable/enable) or reboot the server in order for the changes to start working.
9. Once DNS changes are active you will be able to add additional machines to agentless protection through the Hyepr-V CSV's Virtual Machines page or the Protection Wizard.