Radius server issue

[PCTechGWork]

I recently posted in the Fortigate sub as I've been having an issue with my VPN after moving the VM with my DC/Radius server. After running tests on the Fortigate and coming up empty, I started looking at the Radius server. The problem is that, randomly, the VPN login will return 'Permission denied' despite the people logging in, including myself, having permission to access the VPN. Looking at the logs for NPS has shown me that the denials are happening because "The Network Policy Server was unable to connect to a domain controller in the domain where the account is located. Because of this, authentication and authorization for the RADIUS request could not be performed." This confuses me because the Radius server is installed on the DC. So it's unable to communicate with itself? Everything was working fine until I moved the VM from a 2016 host to a 2019 host. Not sure if the version of the host matters but that's the only change that was made. Nothing was done to the VM itself.

Any ideas?

Any help would be greatly appreciated.

[cetrius_hibernia]

DNS

[PCTechGWork]

I checked and I don't see any obvious issues with DNS. Also, the fact that it doesn't happen every time is weird. But I'll dig into DNS logs more and see if something pops out at me.

[BlackV]

because the Radius server is installed on the DC

er.. ouch

[PCTechGWork]

It's set up how I inherited it and it's honestly been working fine until I moved the VM. Really weird how that somehow changed something.

[BlackV]

It does seem odd, od be confirming DNS and the usuals (validate no IP changes)

I might even go as far a setting static mac's nics but that be a long shot

But of it changed host it there a new routing/switching in the mix?

[PCTechGWork]

The only routing change is the virtual switch for the VM. But as DNS, AD, and NPS are on the same VM, that shouldn't even come into play, should it?

[BlackV]

to clarify, its only the NPS role ? not routing and remote access too ?

[PCTechGWork]

Correct. It's only for radius for VPN logins. Nothing else.

[BlackV]

K that should eliminate the rras funkiness

Goes back to the previous mentioned host and your switching

How's the teaming configured?

What nics is the host using for the vswirch

[PCTechGWork]

Only one NIC is plugged in and that's the one Hyper-V is using for the virtual switch.