Configuration limits

Use the following configuration limits as a guideline when selecting and configuring your virtual and physical environment for Citrix Hypervisor. The following tested and recommended configuration limits are fully supported for Citrix Hypervisor.

  • Virtual machine limits

  • Citrix Hypervisor server limits

  • Resource pool limits

Factors such as hardware and environment can affect the limitations listed below. More information about supported hardware can be found on the Hardware Compatibility List. Consult your hardware manufacturers’ documented limits to ensure that you do not exceed the supported configuration limits for your environment.

Virtual machine (VM) limits

Item Limit
Compute  
Virtual CPUs per VM (Linux) 32 (see note 1)
Virtual CPUs per VM (Windows) 32
   
Memory  
RAM per VM 1.5 TiB (see note 2)
   
Storage  
Virtual Disk Images (VDI) (including CD-ROM) per VM 255 (see note 3)
Virtual CD-ROM drives per VM 1
Virtual Disk Size (NFS) 2040 GiB
Virtual Disk Size (LVM) 2040 GiB
Virtual Disk Size (GFS2) 16 TiB
   
Networking  
Virtual NICs per VM 7 (see note 4)
   
Graphics Capability  
vGPUs per VM 8
   
Devices  
Passthrough USB devices 6

Notes:

  1. Consult your guest OS documentation to ensure that you do not exceed the supported limits.

  2. The maximum amount of physical memory addressable by your operating system varies. Setting the memory to a level greater than the operating system supported limit may lead to performance issues within your guest. Some 32-bit Windows operating systems can support more than 4 GiB of RAM through use of the physical address extension (PAE) mode. For more information, see your guest operating system documentation and Guest operating system support.

  3. The maximum number of VDIs supported depends on the guest operating system. Consult your guest operating system documentation to ensure that you do not exceed the supported limits.

  4. Several guest operating systems have a lower limit, other guests require installation of the Citrix VM Tools to achieve this limit.

Citrix Hypervisor server limits

Item Limit
Compute  
Logical processors per host 448 (see note 1)
Concurrent VMs per host 1000 (see note 2)
Concurrent protected VMs per host with HA enabled 500
Virtual GPU VMs per host 128 (see note 3)
   
Memory  
RAM per host 6 TB
   
Storage  
Concurrent active virtual disks per host 2048
Storage repositories per host 400
   
Networking  
Physical NICs per host 16
Physical NICs per network bond 4
Virtual NICs per host 512
VLANs per host 800
Network Bonds per host 4
   
Graphics Capability  
GPUs per host 8 (See note 4)

Notes:

  1. The maximum number of logical physical processors supported differs by CPU. For more information, see the Hardware Compatibility List.

  2. The maximum number of VMs/host supported depends on VM workload, system load, network configuration, and certain environmental factors. We reserve the right to determine what specific environmental factors affect the maximum limit at which a system can function. For systems running over 500 VMs or when using the PVS Accelerator, we recommend allocating at least 16 GB RAM to the Control Domain (Dom0). For information about configuring Dom0 memory, see CTX134951 - How to Configure dom0 Memory.

  3. For NVIDIA vGPU, 128 vGPU accelerated VMs per host with 4xM60 cards (4x32=128 VMs), or 2xM10 cards (2x64=128 VMs). For Intel GVT-g, 7 VMs per host with a 1,024 MB aperture size. Smaller aperture sizes can further restrict the number of GVT-g VMs supported per host. This figure might change. For the current supported limits, see the Hardware Compatibility List.

  4. This figure might change. For the current supported limits, see the Hardware Compatibility List.

Resource pool limits

Item Limit
Compute  
VMs per resource pool 2400
Hosts per resource pool 64 (See note 1)
   
Networking  
VLANs per resource pool 800
   
Disaster recovery  
Integrated site recovery storage repositories per resource pool 8
   
Storage  
Paths to a LUN 8
Multipathed LUNs per host 150 (See note 2)
Multipathed LUNs per host (used by storage repositories) 150 (See note 2)
VDIs per SR (NFS, SMB, EXT, GFS2) 20000
VDIs per SR (LVM) 1000
Attached VDIs per SR (all types) 600
Storage repositories per pool 400
   
Storage live migration  
(non-CDROM) VDIs per VM 6
Snapshots per VM 1
Concurrent transfers 3
   
XenCenter  
Concurrent operations per pool 25

Notes:

  1. Clustered pools that use GFS2 storage support a maximum of 16 hosts in the resource pool.
  2. When HA is enabled, we recommend increasing the default timeout to at least 120 seconds when more than 30 multipathed LUNs are present on a host. For information about increasing the HA timeout, see CTX139166 - How to Change High Availability Timeout Settings.

Configuration limits