Critical status for WinRM on host status (error 20506) in SCVMM 2012 R2

December 19, 2015 at 6:06 pm in Hyper-V, PowerShell, scvmm by Wim Matthyssen

Some time ago I was contacted by a customer who made the switch from VMware to Hyper-V for running his virtual environment. He already installed a Hyper-V cluster with 4 nodes and was now setting up the System Center Virtual Machine Manger (SCVMM) 2012 R2 management server. That installation ran without any issues, but when he tried to add his Hyper-V hosts he bumped into a critical WinRM error, namely 20506.

After reading the “Error details” and a short investigation on the Hyper-V hosts the problem was found. All Hyper-V hosts ran with the Windows Firewall enabled, but the communication ports for the SCVMM agent were not opened. To fix this I ran the following PowerShell Cmdlets to open up port 80 and 443 which fixed the problem. Keep in mind to run PowerShell as an Administrator.

New-NetFirewallRule -DisplayName "SCVMM Agent 80" -Direction Inbound -LocalPort 80 -Protocol TCP -Action Allow

New-NetFirewallRule -DisplayName "SCVMM Agent 443" -Direction Inbound -LocalPort 443 -Protocol TCP -Action Allow

Set-NetfirewallRule -DisplayName "SCVMM Agent 80" -Enabled True

Set-NetfirewallRule -DisplayName "SCVMM Agent 443" -Enabled True