What’s new since XenServer 7.1

Citrix Hypervisor 8.2 is an LTSR release. If you are on our LTSR stream and are upgrading from XenServer 7.1 CU2, in addition to the features added in Citrix Hypervisor 8.2, you gain all the features that were added in the intervening current releases.

This article contains a list of all new features added since XenServer 7.1 CU2. However, features and capabilities have also been removed since the previous LTSR. For more information about removed and deprecated features, see Deprecations and removals.

Rebranding

Since Citrix Hypervisor 8.0, some of the terms used to describe Citrix Hypervisor products and features have changed. Refer to the following table for the new names.

Previous term New term
XenServer Citrix Hypervisor
XenServer PV Tools Citrix VM Tools
XenMotion Live migration
Storage XenMotion Storage live migration
Enterprise Edition Premium Edition
Free Edition Express Edition

Platform refresh

The Citrix Hypervisor platform has been updated to use the following software:

  • Kernel version: Linux 4.19
  • Xen hypervisor version: 4.13
  • Control domain operating system version: CentOS 7.5

As part of the update to the kernel version, the amount of memory allocated to the control domain (dom0) has increased. For more information, see Memory usage.

The kernel device drivers have also been updated to newer versions. Some hardware that was supported in previous releases might not be compatible with the newer drivers. Before upgrading to Citrix Hypervisor 8.2, check the Hardware Compatibility List.

In addition, the following appliances provided with Citrix Hypervisor have been updated to use CentOS 7.5 as their base operating system:

  • Citrix Hypervisor Conversion manager virtual appliance
  • Workload Balancing virtual appliance
  • Demo Linux virtual appliance

Platform refresh of the Workload Balancing appliance and Conversion Manager appliance

Both of these additional components now include the following improvements:

  • Platform updated to CentOS 7.7
  • Performance gains from using JSON-RPC to communicate with Citrix Hypervisor
  • OpenSSL updated to version 1.1.1
  • Other third-party libraries updated for security and performance improvements
  • TLS 1.2 is now enforced to ensure security

Changes to processor support

The following processors are now supported:

  • Xeon 82xx/62xx/52xx/42xx/32xx CascadeLake-SP
  • AMD EPYC 7xx2(P)
  • Intel Processor families E-21xxG/21xx (Coffee Lake S)

The following legacy processors are no longer supported:

  • Opteron 13xx Budapest
  • Opteron 23xx/83xx Barcelona
  • Opteron 23xx/83xx Shanghai
  • Opteron 24xx/84xx Istanbul
  • Opteron 41xx Lisbon
  • Opteron 61xx Magny-Cours
  • Xeon 53xx Clovertown
  • Xeon 54xx Harpertown
  • Xeon 55xx Nehalem
  • Xeon 56xx Westmere-EP
  • Xeon 65xx/75xx Nehalem-EX
  • Xeon 73xx Tigerton
  • Xeon 74xx Dunnington
  • Xeon E3/5/7 family - Sandy Bridge
  • Xeon E3/5/7 v2 family - Ivy Bridge

For more information, see the Hardware Compatibility List.

Changes to guest support

Citrix Hypervisor no longer supports guests that run in PV mode. For more information, see Deprecations and removals.

For the full list of supported guest operating systems in Citrix Hypervisor 8.2, see Guest operating system support.

Interoperation

Citrix Hypervisor Entitlement for Citrix Virtual Apps and Desktops Service Subscribers

If you have a Citrix Virtual Apps and Desktops Service cloud subscription that enables the use of on-premises Citrix Virtual Apps and Desktops, you are entitled to use Citrix Hypervisor for hosting these apps and desktops.

With this license you can use all of the same premium features as with an on-premises Citrix Virtual Apps and Desktops entitlement. Download a license through the licensing management tool. Install this license on your License Server to use an on-premises Citrix Hypervisor environment with your Citrix Virtual Apps and Desktops subscription.

Enablement for Citrix Virtual Desktops Tablet Mode (Premium Edition)

Citrix Hypervisor and Citrix Virtual Desktops are the only desktop virtualization solution to enable Windows 10 Continuum experience in a virtualized environment. Citrix Hypervisor, with XenDesktop 7.14 or later, allows you to experience tablet mode.

For information on how to enable Citrix Virtual Desktops tablet mode, see the Citrix Virtual Apps and Desktops documentation.

Citrix Director Integration

You can now use Citrix Director version 7.16 and later to access consoles of Server and Desktop OS machines hosted on your Citrix Hypervisor. This way, Citrix Virtual Apps and Desktops users don’t require XenCenter to troubleshoot issues on Citrix Hypervisor-hosted VDAs.

For more information, see the Director documentation.

XenCenter

Citrix Hypervisor Conversion Manager console capabilities are now included in XenCenter

In Citrix Hypervisor 8.0 and earlier, a separate Conversion Manager console was provided. This capability is integrated into XenCenter. The legacy Citrix Hypervisor Conversion Manager console has been retired.

The conversion plug-in that was previously included in the Citrix Hypervisor server installation has also been removed. The removal of this plug-in means that you must use the latest version of XenCenter, which includes the conversion capability, with Citrix Hypervisor 8.2. (You cannot use older versions of the Conversion Manager console with Citrix Hypervisor 8.2.)

However, the Conversion Manager virtual appliance is still required for converting VMware VMs to Citrix Hypervisor VMs. This component is provided on the Citrix Hypervisor Product Download page.

For more information, see Convert VMware workloads.

Automatic application of hotfixes during upgrade or update (Premium Edition)

Citrix Hypervisor simplifies the hotfix application mechanism when upgrading your Citrix Hypervisor hosts or pools to a newer version. The enhanced Rolling Pool Upgrade and the Install Update wizards in XenCenter allow you to install available hotfixes when upgrading to a newer version of Citrix Hypervisor. This enables you to bring your standalone hosts or pools up-to-date with a minimum number of reboots at the end.

You must be connected to the internet during the upgrade process for this feature to work. You can benefit from the automatic application of hotfixes feature when you use the latest XenCenter to upgrade between any supported versions of Citrix Hypervisor or XenServer.

XenCenter: Host Status Visibility

Improvements in XenCenter make it easier to see the licensing status and patching status of your Citrix Hypervisor hosts and pools.

You can now see the licensing status of your hosts and pools in the title bar for the host or pool. Unlicensed pools also show an icon in the tree view. The Updates tab can now show the available updates for your hosts sorted by server. This makes it simpler to see the patching status of all your hosts and pools.

XenCenter alerts for end of life or end of support

XenCenter now alerts you when the version of your managed Citrix Hypervisor servers is approaching end of life or reaches end of life. For more information, see XenCenter Alerts.

XenCenter also alerts you when a Current Release or Cumulative Update is approaching or has passed a date when there will be no further hotfixes issued for that release. Act upon this information and update your environment to a later supported release, to ensure that updates to address any future functional and security related issues can be applied.

Enable and disable read caching from within XenCenter

The read caching feature improves performance on NFS, EXT, or CIF/SMB SRs that host multiple VMs cloned from the same source. This feature can now be enabled and disabled for each individual SR from the XenCenter console. You might want to disable read caching in the following cases:

  • You have no file-based SRs
  • You do not have any cloned VMs
  • You have insufficient memory available to allocate to dom0 to derive any performance benefits

For more information, see Changing SR Properties.

XenCenter Scalability Improvements

The latest XenCenter offers significant improvements in UI responsiveness for customers with large-scale Citrix Hypervisor deployments. This enables customers to better manage their environments when dealing with many pools and VMs.

XenCenter Proxy Authentication

XenCenter already allows the configuration of a proxy server to access the Internet. The latest version of XenCenter adds the ability to specify a user name and password to connect to the proxy server, if the proxy server requires authentication.

Localization for Email Performance Alerts

XenCenter adds the ability to receive performance alert emails in your preferred language. The languages available are English, Simplified Chinese, and Japanese.

VMs

Guest UEFI boot and Secure Boot

Citrix Hypervisor enables VMs running Windows 10 (64-bit), Windows Server 2016 (64-bit), or Windows Server 2019 (64-bit) to boot in UEFI mode. UEFI boot provides a richer interface for the guest operating systems to interact with the hardware, which can significantly reduce Windows VM boot times.

For these Windows operating systems, Citrix Hypervisor also supports Windows Secure Boot. Secure Boot prevents unsigned, incorrectly signed or modified binaries from being run during boot. Secure Boot also reduces the risk that malware in the guest can manipulate the boot files or run during the boot process.

For more information, see Windows VMs.

Scheduled Snapshots

The scheduled snapshots feature provides an easy-to-use backup and restore utility for critical VMs. This enables customers to configure their environment to automatically create VM snapshots at specified intervals. This helps guard against unforeseen data corruption issues, system crashes, or user errors, by providing a last-known working version of the VM.

BIOS Asset Tags

You can now use the xe CLI or the API to specify BIOS asset tags on a per VM basis. This enables you to track assets more easily and leads to smoother management and licensing.

Graphics

Multiple vGPU (Premium Edition)

For NVIDIA GPUs and drivers that support multiple vGPU, you can configure a single VM to use multiple virtual GPUs concurrently. These additional vGPUs can be used to perform computational processing. Only certain vGPU profiles can be used and all vGPUs attached to a single VM must be of the same type.

For more information, see Graphics Overview.

Support for disk and memory snapshots for vGPU-enabled VMs (Premium Edition)

When a disk and memory snapshot of a vGPU-enabled VM is taken the state of the VM includes the vGPU state. This vGPU state is restored when the VM is resumed from the snapshot.

vGPU live migration (Premium Edition)

You can migrate VMs with vGPUs between hosts without shutting the VMs down, allowing administrators to take advantage of live migration with vGPUs attached. vGPU live migration is available for supported software and graphics cards from GPU vendors. For more information, see the Hardware Compatibility List.

In addition to live migration, storage live migration and VM suspend with vGPUs attached have also been enabled in this release for VMs using supported software and graphics cards.

AMD MxGPU (Premium Edition)

With the addition of support for AMD’s virtualized graphics solution, Citrix Hypervisor continues its leadership in the virtualized graphics domain.

Building on our first-to-market partnerships with NVIDIA vGPU and Intel GVT-g, Citrix Hypervisor becomes the only hypervisor platform to support the virtualization solutions of all three graphics vendors. Citrix Hypervisor customers can use AMD MxGPU on 64-bit versions of Windows 10, Windows Server 2016, and Windows Server 2019 VMs.

With the addition of support for AMD’s virtualized graphics solution, Citrix Hypervisor continues its leadership in the virtualized graphics domain. Citrix Hypervisor customers can use AMD MxGPU on provided by the AMD FirePro S7100-series GPUs. See the list of supported hosts on the Hardware Compatibility List.

Storage

Changed Block Tracking (Premium Edition)

Changed block tracking provides a set of features and APIs that enable third-party software vendors to develop fast and space-efficient incremental backup solutions.

With changed block tracking, you need less disk space because, instead of handling and storing large VDIs, you can store space-efficient metadata-only snapshot files.

For more information, see Changed Block Tracking.

Thin provisioning for shared block storage - GFS2 (Premium Edition)

Citrix Hypervisor makes thin provisioning available to customers using block-based storage accessed through an iSCSI software initiator or Hardware HBA. Thin provisioning is implemented by using GFS2.

Thin provisioning makes better use of the available storage by allocating disk storage space to VDIs because data is written to the virtual disk, rather than allocating the full virtual size of the VDI in advance. Thin provisioning enables you to significantly reduce the amount of space required on a shared storage array, and with that your Total Cost of Ownership (TCO).

The following use cases can benefit from thin provisioning:

  • Server virtualization
  • Citrix Virtual Apps and Desktops (both persistent and non-persistent)
  • Large-scale Cloud deployments

Thin provisioning for shared block storage is of particular interest in the following cases:

  • If you want increased space efficiency, because images are sparsely and not thickly allocated.
  • If you want to reduce the number of I/O operations per second on your storage array. The GFS2 SR is the first SR type to support storage read caching on shared block storage.
  • If you use a common base image for multiple virtual machines, because the images of individual VMs then typically use even less space.
  • If you use snapshots, because each snapshot is an image and each image is now sparse.

For more information, see GFS2.

Create VDIs greater than 2 TiB (Premium Edition)

You can also create virtual disk images on GFS2 SRs that are larger than the previous 2 TiB limit.

Primary disks for Windows VMs are in Master Boot Record (MBR) format. MBR limits the maximum addressable storage space of a disk to 2 TiB. To use a greater than 2 TiB disk for a Windows VM, create it as the secondary disk for the VM and select GUID Partition Table (GPT) format

Support for SMB version 3 for ISO SRs

Citrix Hypervisor now supports SMB version 3.0 as the default method of connecting to ISO SRs. SMB version 3.0 is more secure and robust than SMB version 1.0.

SMB version 1.0 is still supported and Citrix Hypervisor can fall back to using this protocol version if version 3.0 is not available. You can mount ISO SR using SMB version 1.0 using the CLI. However, we recommend that you use SMB version 3.0 where it is available.

Performance improvements

Increased configuration limits

The following configuration limits have been increased:

  • The maximum host RAM is now 6 TB
  • The maximum number of logical processors per host is now 448 CPUs

For more information, see Configuration limits.

Supported Pool Size Increased to 64

Citrix Hypervisor now supports up to a maximum of 64 hosts in a pool. Increased pool size helps in a more efficient management of VMs and provides greater flexibility when using High Availability.

Note:

This feature is not available to users of the Express Edition.

Improved performance for VM imports and exports that use the XVA format

Changes to the checksum used in XVA files in Citrix Hypervisor 8.1 provided significant performance improvements when importing or exporting VMs using this new checksum algorithm.

The reduction in the time it takes to import or export a VM depends on the specific hardware of the machine. The larger the VM the larger the performance improvement seen.

Use the latest XenCenter to manage exported VMs that use XVA files with the new checksum algorithm.

If you have a custom application that relies on the format of the checksum included in the XVA file, update your application to use the new format. The checksum has changed to use the xxHash algorithm. The checksum file name now ends with the extension .xxhash.

Storage performance improvements

Storage performance is significantly improved when I/O is performed in block sizes larger than 64 KiB on an NFS SR.

Multipage support is now available in non-GFS2 SRs for better storage performance. If your Windows VM has the Citrix VM Tools installed, the VM uses multipage support automatically.

To enable multipage support on a Linux VM complete the following steps:

  1. First, verify that your kernel supports the max_ring_page_order parameter. Run the following command:

    modinfo xen_blkfront | grep max_ring_page_order
    

    If this command returns an empty response, your kernel does not support this feature. Do not proceed with these steps.

  2. Take a snapshot of your VM.

  3. On the VM, run the following command:

    echo 'options xen_blkfront max_ring_page_order=3' >/etc/modprobe.d/xen_blkfront.conf
    
  4. Depending on your Linux distribution, run one of the following commands:

    • For RHEL, CentOS, or Oracle Enterprise Linux: dracut -f -v
    • For Debian-based distributions: update-initramfs -u -k all
  5. Reboot your VM.

New Windows I/O drivers with improved performance

Updated Windows I/O drivers with the major version 9 (9.x.x.x) are provided with this release of Citrix Hypervisor for the following operating systems: Windows 8.1, Windows 10, Windows Server 2012, Windows Server 2012 R2, Windows Server 2016, Windows Server Core 2016, Windows Server 2019, Windows Server Core 2019. These Windows I/O drivers include several performance improvements.

These drivers are also available through Windows Update for Premium Edition customers.

Windows I/O drivers with the major version 8 (8.x.x.x) are still provided for the older supported Windows operating systems. These drivers do not contain the performance improvements.

XenCenter, C# SDK, and PowerShell module performance improvements

XenCenter, the C# SDK, and the PowerShell module now use JSON-RPC instead of XML-RPC to communicate with the Citrix Hypervisor host. This change improves the performance when interacting with Citrix Hypervisor, especially when connecting to a pool.

Security improvements

Install a TLS certificate on your Citrix Hypervisor server

Citrix Hypervisor now enables easy installation of server TLS certificates.

The Citrix Hypervisor server comes installed with a default TLS certificate. However, to use HTTPS to secure communication between Citrix Hypervisor and Citrix Virtual Apps and Desktops, you must install a new certificate. The certificate authority issuing the certificate must be trusted by the Citrix Virtual Apps and Desktop installation.

This feature provides a mechanism to update host certificates that does not require the user to have access to the Citrix Hypervisor server file system. It also verifies that the certificate and key files are valid and in the correct format.

You can install a TLS certificate on the Citrix Hypervisor server by using one of the following methods:

This feature also provides XenCenter alerts when a server TLS certificate is about to expire. For more information, see System Alerts in the XenCenter documentation.

Enforcing use of the TLS 1.2 protocol

Citrix Hypervisor now enforces the use of the TLS 1.2 protocol for any HTTPS traffic between Citrix Hypervisor and an external network. All Citrix Hypervisor components use the TLS 1.2 protocol when communicating with each other.

As part of this feature the legacy SSL mode and support for the TLS 1.0/1.1 protocol have been removed. Ensure you disable legacy SSL mode in your pools before upgrading or updating them to Citrix Hypervisor 8.2. If you have any custom scripts or clients that rely on a different protocol, update these components to use TLS 1.2.

Bromium Enhanced Security (Premium Edition)

You can use Bromium Secure Platform (now HPE) on Windows VMs running on Citrix Hypervisor.

Bromium Secure Platform provides protection at the endpoint against all advanced malware. This protection is transparent to the end user and has no impact on user experience or system performance. For more information about the advantages of Bromium Enhanced Security, see the Bromium website.

General

Disaggregation of the Citrix VM Tools

The Citrix VM Tools are now provided as two separate components on the Citrix Hypervisor download page:

  • Citrix VM Tools for Windows
  • Citrix VM Tools for Linux

As a result, the guest-tools.iso file has been removed from the Citrix Hypervisor installation.

Providing the tools as a separate component removes the need for hotfixes to apply updates to a tools ISO stored on the Citrix Hypervisor server.

For more information, see Linux VMs and Windows VMs.

Networking SR-IOV: Passthrough of Virtual Functions (Premium Edition)

Citrix Hypervisor can now use Single Root I/O Virtualization (SR-IOV) that allows a single PCI device to appear as multiple PCI devices on the physical system.

You can assign one or more NIC Virtual Functions to a VM, allowing its network traffic to bypass the virtual switch. When configured, each VM behaves as though it is using the NIC directly, reducing processing overhead, and improving performance. For more information, see Using SR-IOV enabled NICs.

USB Passthrough (Premium Edition)

Citrix Hypervisor now supports passing through individual, physical USB devices to a VM. The VM’s OS can use the physical USB device as a local USB device.

IGMP Snooping for IPv4 Multicast Support (Premium Edition)

You can now use IPv4 multicast to send data to VMs that are members of a multicast group built by using the IGMP protocol.

When enabled, this feature prevents multicast traffic being sent to all VMs and causing unnecessary load on host devices by requiring them to process packets they have not solicited. Instead, when multicast traffic comes into the Citrix Hypervisor host, Citrix Hypervisor detects the group of this traffic and forwards the traffic to guest VMs that subscribe to this group. This feature improves the performance of multicast and is especially useful for bandwidth-intensive IP multicast applications such as IPTV.

VLAN Tagging

Citrix Hypervisor supports VLAN tagging on management and storage interfaces. You can create a pool of Citrix Hypervisor hosts to communicate on a VLAN network.

Additionally, you can upgrade or perform a fresh installation of the Citrix Hypervisor host to your management interface on a tagged VLAN. This enables you to provision your Citrix Hypervisor host management interface on a tagged VLAN network and access the host on the same VLAN network.

New structure for the product documentation

The Citrix Hypervisor product documentation is now provided as an HTML documentation set instead of PDFs.

  • Use the table of contents on the left to navigate to the information that you need
  • Use the search box in the top-right to search for specific information
  • See an outline of the information in each article in the ‘In this article’ box
  • Download all content as a PDF for offline viewing by using the ‘View PDF’ button

All information from the PDF guides is included in the new documentation structure. For example, content from the Installation Guide is available in the Install section and content from the VM User’s Guide is available in the VMs section. The main subjects in the Administrator’s Guide are not included in a separate ‘Administer’ section and are instead listed in the table of contents.

Web-based help for XenCenter

Documentation for XenCenter is now available online at the Citrix Product Documentation website.

This online documentation replaces the in-product help. Now, when you press F1 in the UI or choose to access contextual help, the relevant article opens in your default browser. These articles are also available as a PDF for offline viewing. Use the View PDF button to download the PDF.

These web-based articles offer you the most accurate and up-to-date content.

What’s new since XenServer 7.1