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HOWTO UCC

IGEL OS UCC Configuration Guide

Addendum to UCC Guide

UCC Hardware Requirements

UCC Type Hardware Limits Link to Vendor
Zoom VDI - ANY (Citrix / Horizon / AVD) Dual Core < 2GHz base clock = LIMITED to 9 video streams
Dual Core AMD chips with 2x in name = LIMITED to 6 video streams
Dual Core >= 2GHz clock (or Intel i5/i7 < 2GHz) = 25 video streams
Quad Core or higher (any clock speed) = 25 video streams		 Zoom VDI Client Hardware Requirements

Zoom VDI client features comparison
MS Teams VDI (Citrix) Dual Core >= 1.8GHz base clock speed for 720p 1:1 call
Dual or Quad Core >= 1.8GHz with 2.9GHz boost for many:many call		 Teams VDI for Citrix Client Hardware Requirements
MS Teams VDI (Horizon) Dual Core >= 2.4GHz base clock speed Teams VDI for Horizon Client Hardware Requirements
MS Teams VDI (AVD) Dual Core >= 1.6GHz base clock speed
4GB of Available memory		 Teams VDI for AVD Client Hardware Requirements
Webex VDI - ANY (Citrix / Horizon / AVD not yet available) Any 64-bit x86 + 2GB RAM Webex VDI Client Hardware Requirements

Latest Known Good Settings for Citrix

NOTE: If you are experiencing an issue with Citrix, test with one of these profiles assigned for OS 11 or OS 12. It may not fix the issue, but it is a good place to start.

Tested with IGEL OS 11.09.160 and IGEL OS 12.3.0.

These are known good settings for Citrix browser content redirection, HDX webcam redirection, and also a setting that if you are in a meeting (Zoom VDI, Teams, Webex Meetings VDI) and are inactive the screensaver will not kick in.

This setting also work for VMware and may also work for AVD: debug.tools.igel-screensaver-monitor.enable

Virtual Background for Unified Communication Apps in IGEL OS

USB Devices and UCC

In general, USB redirection is not needed for standard functionality such as audio, video, HID input, etc. However, in some special circumstances, a device may need to be redirected into a VDI session for full functionality, or if it requires a specific driver to function.

Citrix with the Jabra Evolve 20 to enable the call button on the headset:

Setup call button on Jabra Evolve 20 with Native USB Redirection enabled via following device rule:

Rule=Connect, VID= 0B0E, PID=0300, extra config = split=1 intf=03

Cisco Webex Meetings VDI Optimization

There have been some changes with Webex Meetings VDI, and now instead of using a separate installer for Webex Meetings, they are now bundled.

In short, if you are using Webex VDI (Teams), and Webex Meetings VDI, and want both to be optimized, make sure to use the bundle installer from here.

This is the latest version of the documentation

Auto-upgrade disabled:

VDI client in a persistent VDI setting with autoupgrade disabled

msiexec /i c:\users\[username]\Downloads\WebexBundle.msi ALLUSERS=1 ENABLEVDI=2 AUTOUPGRADEENABLED=0 FORCELOCKDOWN=NeverUpdate

VDI client in a non-persistent VDI setting with autoupgrade disabled

msiexec /i c:\users\[username]\Downloads\WebexBundle.msi ALLUSERS=1 ENABLEVDI=2 AUTOUPGRADEENABLED=0 ROAMINGENABLED=1 FORCELOCKDOWN=NeverUpdate

Cisco Webex Meetings VDI & Cisco Webex App VDI Compatibility Lists

Compatibility lists for Cisco Webex Meetings VDI & Cisco Webex App VDI:

Webex Meetings Virtual Desktop Infrastructure release notes

Webex App | VDI release notes

Steps to automatically update

Must keep up the race to stay on latest version of IGEL OS so as to not fall out of sync with backend releases as noted in links above.

For example, when the latest version was 43.5, then IGEL OS 11.08.248 is needed since it includes the plugin for Cisco Webex Meetings VDI plugin 42.10.

Citrix HDX Webcam redirection for 64-bit applications. HowTo guide!

Sample profile to use with 11.08.360 and above for HDX webcam redirection. Tested with Logitech C920e, Logitech HD Pro C920 and Logitech C925.

HOWTO-UCC-Citrix-Global-64bit-Webcam-Delay-Type-2-Manual-Config-Logitech-HD-Pro-Webcam-C920

KB: HDX Multimedia Settings for an IGEL OS Citrix Session

Also, please note that if using Chromium to connect to Citrix to set the following in the registry for the session:

  • Set multimedia.gstreamer.version to 1.x
  • Set sessions.chromium%.gstreamer_version to 1.0

Cisco Webex App for VDI using IGEL OS and the known limitation with "ring all devices"

NOTE: Cisco fix planned for 43.6 version scheduled June 2023.

  • On Linux VDI clients, an incoming call does not ring all devices (including speakers on the thin client) even if that option is selected in Webex App on the HVD host. Only the audio device selected on the HVD plays the ringtone.

Wacom Tablets

IGEL OS 11 includes drivers for Wacom tablets.

The Linux Wacom Project manages the drivers, libraries, and documentation for configuring and running Wacom tablets under the Linux operating system. These drivers are pre-installed in IGEL OS 11 and provide out-of-the box support for a virtually all Wacom tablets and TabletPCs.

Bandwidth Requirements for Various Types of Users

When determining minimum bandwidth requirements for Citrix / VMware, plan with the following estimates:

  • 100 to 150Kbps average bandwidth for a basic office productivity desktop: typical office applications with no video, no 3D graphics, and the default Windows and Citrix / VMware settings.
  • 50 to 100Kbps average bandwidth for an optimized office productivity desktop: typical office applications with no video, no 3D graphics, with Windows desktop settings optimized and Citrix / Horizon optimized.
  • 400 to 600Kbps average bandwidth for virtual desktops utilizing multiple monitors, 3D, Aero, and Microsoft Office.
  • 500Kbps to 1Mbps minimum peak bandwidth to provide headroom for bursts of display changes. In general, size your network using the average bandwidth, but consider peak bandwidth to accommodate bursts of imaging traffic associated with large screen changes.
  • 2Mbps per simultaneous user running 480p video, depending upon the configured frame rate limit and the video type.

Example -- Branch or Remote Office Scenario

  • Users have basic Microsoft Office productivity applications, no video, no 3D graphics, and USB keyboards and mouse devices.
  • The bandwidth required per typical office user on Horizon is from 50-150Kbps.
  • The T1 network capacity is 1.5Mbps.
  • Bandwidth utilization is 80 percent (.8 utilization factor).

Formula for Determining the Number of Users Supported

  • In the worst case, users require 150Kbps: (1.5Mbps*.8)/150Kbps = (1500*.8)/150 = 8 users
  • In the best case, users require 50Kbps: (1.5Mbps*.8)/50Kbps = (1500*.8)/50 = 24 users

Result

  • This remote office can support between 8 and 24 concurrent users per T1 line with 1.5Mbps capacity.

Sample Guideline for VDA workloads – Number of users per server

Guideline for VDA workloads – based on CPU Cores (Servers have 2 CPUs with 18 cores per CPU - Total of 36 cores)

  • HSA (Hosted Shared Applications):
    • Light -- 4 applications running at the same time (12:1 users to core) (12 * 36 = 432 users per server)
    • Medium -- 4 applications running at the same time (10:1 users to core) (10 * 36 = 360 users per server)
    • Heavy -- 4 applications running at the same time (8:1 users to core) (8 * 36 = 288 users per server)
  • HSD (Hosted Shared Desktops - Windows Server 2016) (8:1 users to core) (follow Memory guideline)
  • NVD (Non-Persistent Desktops - Windows 10) (5:1 users to core) (follow Memory guideline)
  • PVD (Persistent Desktops - Windows 11 (should be 5% of total workload) (4:1 users to core) (follow Memory guideline)

Guideline for VDA workloads – based on server memory (768GB RAM)

  • HSA (Hosted Shared Applications):
    • Light -- 4 applications running at the same time (12:1 users to core) (follow CPU cores guideline)
    • Medium -- 4 applications running at the same time (10:1 users to core) (follow CPU cores guideline)
    • Heavy -- 4 applications running at the same time (8:1 users to core) (follow CPU cores guideline)
  • HSD (Hosted Shared Desktops - Windows Server 2016) (8:1 users to core) (768GB / 3GB per user = 256 users per server)
  • NVD (Non-Persistent Desktops - Windows 11) (5:1 users to core) (768GB / 6GB per user = 128 users per server)
  • PVD (Persistent Desktops - Windows 11 (should be 5% of total workload) (4:1 users to core) (768GB / 8GB per user = 96 users per server)

Citrix: Design Decision: Single Server Scalability

Citrix Browser Content Redirection (BCR)

Browser content redirection prevents the rendering of webpages in the allow list on the VDA side. This feature uses Citrix Workspace app for Linux to instantiate a corresponding rendering engine on the client side, which fetches the HTTP and HTTPS content from the URL.

Google Meet in VDI

Steps to optimize Google Meet in VDI:

MS Teams Optimization Feature Compatibility Matrix for Horizon 7 and Horizon 8 Recent Releases. (86475)

IGEL adds Citrix Device Posture Service support – Higher security and extended control of access

IGEL has integrated with the Device Posture Service (DPS) team at Citrix to add the functionality of validating that the endpoint fulfills requirements set to access the Citrix Cloud environment.

Device Posture service with IGEL OS offers conditional access control to your Citrix Cloud environment and is a key component to Zero Trust based access.

IGEL adds Citrix Device Posture Service support – Higher security and extended control of access. IGEL + Citrix = Better together!

Unexpected Keyboard Layout in a Citrix Session

When a Citrix session has started, the keyboard layout changes in an unexpected way. On the local system, the keyboard layout may still be as expected.

Touchpad pressure-based touch detection

Sample profiles to address touchpad sensitivity issue.

Citrix HDX service fails on 29th February

>> Run the below command from an administrative command prompt [Start > cmd > right click and run as admin]

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net stop w32time & date 03-01-2024 & net start CtxHdxWebSocketService & net start w32time

IGEL OS 11.09.217 / 11.09.260 Citrix Multiple Audio Device Support / Unified Communications Issue

NOTE: Fixed with 11.09.313 release on 17 April 2024

  • Issue is the multiple audio device support is not working
  • Zoom VDI/Microsoft Teams will not work when the device is in the problem state

Workaround:

  • Configure the following as a final desktop command: systemctl restart igel-citrix-icaconfig.service
  • If you have a session that is configured to autostart, also add an autostart delay of 5 seconds.

How to disconnect all Bluetooth devices at reboot / shutdown

Horizon with Black Screen with Flickering White Spots

This is a quirk of current Horizon linux clients which show this when there's no compositor in the window manager.

In IGEL OS the compositor is off by default because it may have side effects on older / slower devices.

Here is registry setting: windowmanager.wm0.variables.usecompositing

Citrix Workspace cannot find a valid smart card certificate

OS 12 issue inserting smart card and Citrix Workspace starts and then error message: Citrix Workspace cannot find a valid smart card certificate.

If the smart card is removed and reinserted then Citrix Workspace app recognizes the smart card and login can proceed.

Issue the following command via IGEL KB: Before Desktop Start

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sed -i "/SinglePin=0/c SinglePin=1" /etc/netid.conf