I shut down firewall service and network connectivity was lost, why?

Question

_{Friday, January 29, 2016 8:13 PM}

I shut down the firewall service on a server running 2012r2 inside a VM.  Immediately the VM lost connectivity and now I can't log back in.

Can someone explain why this might have happened?

Thanks

All replies (5)

_{Friday, January 29, 2016 8:36 PM ✅Answered}

Sounds like you may have disabled the firewall service? In short, it will appear from outside as though the server has been disconnected from the network including RDP, although network tasks initiated from that server may still function.

https://technet.microsoft.com/en-us/library/cc766337%28v=ws.10%29.aspx?f=255&MSPPError=-2147217396

I'd console in to reenable it.

Regards, Dave Patrick ....
Microsoft Certified Professional
Microsoft MVP [Windows]

Disclaimer: This posting is provided "AS IS" with no warranties or guarantees , and confers no rights.

_{Friday, January 29, 2016 8:16 PM}

I'll go with gremlins for 500 Bob.

_{Friday, January 29, 2016 8:49 PM}

Disabling the firewall service (as opposed to changing the firewall rules) affects network routing.

https://technet.microsoft.com/en-us/library/cc733276(v=ws.10).aspx

It sits as a filter driver in the stack and is actually an important piece of network packet routing.

Disabling the firewall rules is a vastly different thing than disabling the entire service.

BTW - this is not a Hyper-V issue,  it is an OS issue.

Let's see if we can get you better detail..

Brian Ehlert
http://ITProctology.blogspot.com
Learn. Apply. Repeat.

_{Monday, February 1, 2016 7:38 AM}

Hi newbieatVMs,

     Dave and BrianEh provides most information about this situation.

     Please do not disable Windows Firewall by stopping the service. Instead, use one of the preceding procedures (or an equivalent Group Policy setting) to turn the firewall off. If you turn off the Windows Firewall service, you lose other benefits provided by the service, such as the ability to use Internet Protocol security (IPsec) connection security rules, Windows Service Hardening, and network protection from attacks that employ network fingerprinting. Stopping the service associated with Windows Firewall is not supported by Microsoft.

Best Regards，

Cartman

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_{Friday, April 22, 2016 5:26 PM}

Hello newbieatVMs

Windows Firewall service is dependent on Base Filtering Engine service.

Windows Firewall service should never be turned off as lot of other services like IPSec, Direct Access, etc are dependent on it.

You can rather turn off all the Windows profiles from the GUI wf.msc or using the command: netsh advfirewall set allprofiles state off.

Regards

Arijit Paul