FAQ

What are the first things to look for when a connection between client and server fails?

Here are some ways to resolve the connection failure:

• Verify that the IP address is correct for the server.

• Verify that the syntax for the IP is correct if using command-line format. For example, a server at IP 10.0.0.6 would be specified as -s 10.0.0.6.

• Check the client and server logs for matched versions.

• Verify that the CloudXR server is running.

• Verify that the app storage permissions are enabled for the CloudXR app on Android clients.

• If using config file for command-line/launch options, verify the file CloudXRLaunchOptions.txt exists in the proper location (see Command-Line Options).

What GPUs are supported on CloudXR?

Please consult the CloudXR Server System Requirements.

What GPUs are supported on the Windows CloudXR client?

Please consult the CloudXR Client System Requirements.

Does the CloudXR server driver support virtual GPUs (vGPUs)?

Yes. Please consult the CloudXR Server System Requirements for more details, particularly supported vGPU software and driver versions.

With CloudXR, can you use vGPU to run multiple VR users on one GPU?

Yes, but note that only one CloudXR server session can run per running Windows instance, i.e., to have multiple users on a single vGPU, the vGPU will need to be set up to be shared between multiple virtual machines.

Note that the performance of vGPU with multiple users is highly application dependent. The following table is provided as general guidance only for moderate XR workloads and is not formalized support:

GPU Model	# Users	vGPU License Types	Installation Types
P4000	1	N/A	Workstation / PC
P5000	1	N/A	Workstation / PC
P6000	1	N/A	Workstation / PC
GP100	1	N/A	Workstation / PC
P100	1	RTX Virtual Workstation	Virtualised / Cloud Hosted
P40	1	RTX Virtual Workstation	Virtualised / Cloud Hosted
GV100	1	N/A	Workstation / PC
V100	2	RTX Virtual Workstation	Virtualised / Cloud Hosted
T4	1	RTX Virtual Workstation	Virtualised / Cloud Hosted
RTX4000	1	N/A	Workstation / PC
RTX5000	1	N/A	Workstation / PC
RTX6000	1	N/A	Workstation / PC
RTX6000	2	RTX Virtual Workstation	Virtualised / Cloud Hosted
RTX6000 Passive	2	RTX Virtual Workstation	Virtualised / Cloud Hosted
RTX8000	1	N/A	Workstation / PC
RTX8000	2	RTX Virtual Workstation	Virtualised / Cloud Hosted
RTX8000 Passive	2	RTX Virtual Workstation	Virtualised / Cloud Hosted
A6000	1	N/A	Workstation / PC
A6000	2	RTX Virtual Workstation	Virtualised / Cloud Hosted
A40	2	RTX Virtual Workstation	Virtualised / Cloud Hosted

Which operating systems are supported?

Please consult the System Requirements for details.

Are there any restrictions on the GPU driver?

Yes, particularly for vGPU configurations. Please consult the System Requirements for details.

What headsets are officially supported?

Please consult the CloudXR Client System Requirements for details.

Which types of apps are supported?

NVIDIA CloudXR supports VR streaming of any SteamVR application (OpenVR or OpenXR), and tablet AR streaming of specialized SteamVR applications. See SteamVR Server Requirements.

Is protected content (i.e. HDCP tagged) supported?

No.

What are the restrictions on redistribution of the SDK binary files?

For details about licensing, see the EULA that is packaged with the SDK.

What are the Steam and SteamVR requirements?

• Steam is required with the consumer version of SteamVR.

• SteamVR Enterprise is supported where Steam is not required to be installed.

Do I need to reinstall the client if the server is reinstalled?

No, but the client and server need to be the same NVIDIA CloudXR SDK version.

Can multiple NVIDIA CloudXR SDK clients be connected to an NVIDIA CloudXR SDK server driver or an NVIDIA CloudXR client be connected to multiple servers simultaneously?

No. The relationship between an NVIDIA CloudXR SDK client and an NVIDIA CloudXR SDK server driver is a one-to-one relationship. If multiple connections to a single system are required, consider running multiple VMs with virtualized GPUs (vGPUs).

Does NVIDIA CloudXR work over wireless networks?

Yes, but the quality of the wireless network is important. See CloudXR Network Requirements and CloudXR Network Setup.

What are the network speed requirements for the connection?

See CloudXR Network Requirements.

Which ports are required for the client and the server?

See CloudXR Network Requirements.

The CloudXR installer will open the ports that are associated with CloudXR in the Windows Firewall. If the connection cannot be established, turn Windows Firewall off temporarily and try again.

How are the individual streams for each eye synchronized?

The frames for the eye streams are sent with a frame number, which the client uses to synchronize the frames.

Why am I facing connection issues even though the firewalls are turned off and/or the required ports are open?

One possible issue is compatibility problems with Remote Desktop Software. Otherwise, look at other installed network applications on the client or server that might be consuming or blocking ports.

Does the OpenVR application need to be modified to work with CloudXR for VR?

If the application queries the device parameters via OpenVR, and does not hard-code headset parameters, it will work without modifications. CloudXR will forward the client device specifications, such as a resolution, a field of view, and the refresh rate.

Does CloudXR support client-server authentication?

Client-side authentication isn’t part of the CloudXR SDK. This would require implementation outside of the CloudXR connection.

Does CloudXR encrypt data streams?

CloudXR does not currently securely encrypt any streams, including setup, input, audio, and video.

What other command-line options are available for the clients?

See Command-Line Options for more information.

How do I capture ETL streaming traces so that the CloudXR support team can analyze them?

See ETL Traces for information about how to capture ETL traces.

Why is the order of launching CloudXR important?

The order is required because the server does not have the necessary information to feed to the game until after the connection is made unless it has been pre-configured on the server. This situation is like starting an app without first plugging in your virtual reality (VR) device.

The order is:

1. Start SteamVR on the server.

2. Start the CloudXR client to make the connection.

3. Start the game/app on the server.

What if I am not hearing any audio from the server when using the Windows client?

One possible issue might be that there are multiple audio outputs on the client system.

• In this case, ensure that the headset setting is being used. This setting can be viewed/changed by left clicking the sound control in the system tray and selecting the desired output in the list just above the volume control.
• Also, sometimes, it helps to have a real audio output device, speakers, or headphones attached to the server.
• If the Graphics driver is updated, ensure that a CloudXR SW reinstall is completed after this update with the audio capture driver checkbox selected.

Another possibility is that there are no audio facilities on the server, such as there are for a cloud server. In this case you can select the NvVAD device to provide audio capture for sending to the client. This should be a selection in the audio popup in the lower right corner of the task bar.

What if I am not hearing any audio from the server?

Ensure that the Audio Capture driver is installed on the server as part of the CloudXR installation.

How do I get access to the Steam VR menu while streaming?

The client application can send a system menu button press to the server.

In the Windows client sample application, this has been set up as follows:

• For Quest, click the left controller menu button.

• For HTC VIVE, click the left menu button.

• For Index, click the left B button.

How can I determine the ping time from a stand-alone headset to the CloudXR server?

With the stand-alone headset that is connected to a Windows system, run the following ADB command:

adb.exe shell ping <Server IRL>

Will my CloudXR server properly stream to clients while a VR device is connected to it?

For the NVIDIA CloudXR server driver to be activated, before you start SteamVR, ensure that the VR device, such as VIVE, is disconnected from the system.

Why does my client microphone content not stream to the server?

If you are using an Android device, make sure that microphone permission has been granted to the application.

What is another possible reason I can’t connect to the Server with my client?

In some rare cases, the CloudXR SteamVR add-on might get disabled.

To verify that CloudXR is enabled:

1. In the SteamVR menu, select Settings > Advanced and select Manage Add-ons.

2. Ensure that CloudXRRemoteHMD is set to on and that only one item like this is present.

Why am I getting a green video stream on the client?

This can be caused by any application on the server that prevents capture of the source video. One specific cause may be if you are remotely controlling your server – for more details, see Remote Desktop Software. It also can be caused by certain screen recording applications.

Does CloudXR support arm-64?

Yes. As of CloudXR 4.0, CloudXR’s Android library is only tested with 64-bit arm.

Are CloudXR server/client binaries compatible with the earlier versions?

No, these server/client binaries are not compatible. Ensure you have the exact matching client and server versions.

Are there any restrictions that would prevent CloudXR from running in a Network Address Translation (NAT) or Network Address Port Translation (NAPT) environment ? Is port forwarding supported?

There are no restrictions. Your results may vary depending on your network configuration details.

Is there a way to proxy the network traffic through Citrix virtual channels when a direct connection between the client and server is needed?

No, currently CloudXR will not work with Citrix VCs.

Is there a need for a CloudXR Server plugin for Unreal Engine applications?

No. After you install the CloudXR server driver, you can use the existing OpenVR plugin and CloudXR will appear as a regular headset. CloudXR works transparently with the existing OpenVR support built into the engine.

What is the maximum resolution to use CloudXR on Android? If I have a device with an 8K decoder, can I play 8K content in the CloudXR?

For the CloudXR library, you can specify the maximum resolution when you create the receiver instance. For the CloudXR sample apps, the display resolution * 1.2x is used as max res and you can override that from the config file. Currently, the resolution is limited to 4k.

Is there a current bandwidth cap in CloudXR for video?

The default cap is 50 Mbps per eye, so 100 Mbps total. This can be modified using parameters within the API.

Is WebAR or WebXR supported with CloudXR?

Currently, WebAR and WebXR are not supported.

Is eye-tracking supported with CloudXR?

No, currently eye-tracking is not supported.

How is the CloudXR server add-on added to SteamVR? How can I add it back if it gets removed?

During CloudXR installation, the CloudXR server add-on is added to SteamVR with the vrpathreg.exe utility that is bundled with Steam. You can read it by manually running the command.

<Steam-install-dir>\steamapps\common\SteamVR\bin\win64\vrpathreg.exe
       adddriver "<CloudXR-install-dir>\VRDriver\CloudXRRemoteHMD"

Why does the SteamVR headset icon not show the “CXR” letters when connecting the headset?

This is because the SteamVR cache does not realize the icons have been updated. You can delete the cached icons by navigating to C:\Program Files\NVIDIA Corporation\CloudXR\VRdriver\CloudXRRemoteHMD\resources\icons and deleting the files with hex values in their names.

Can CloudXR stream Stereo RGBA for devices that support that?

No, currently CloudXR can only stream Stereo in raw RGB. The only RGBA support is for Mono AR streams.

Does CloudXR have any support for scene Depth?

No, currently CloudXR Server does not support streaming Depth surfaces, and the Client samples do not show how to capture AR Depth information.

Do you support the HoloLens 2?

No. Please consult the CloudXR Client System Requirements for devices supported.