// Module included in the following assemblies:
//
// * virt/install/preparing-cluster-for-virt.adoc

:_mod-docs-content-type: REFERENCE
[id="virt-ibm-z-compatibility_{context}"]
= {ibm-z-title} and {ibm-linuxone-title} compatibility

[role="_abstract"]
You can use {VirtProductName} in an {product-title} cluster that is installed in logical partitions (LPARs) on an {ibm-z-name} or {ibm-linuxone-name} (`s390x` architecture) system.

Some features are not currently available on `s390x` architecture, while others require workarounds or procedural changes. These lists are subject to change.

Currently unavailable features::
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The following features are currently not available on `s390x` architecture:
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* Memory hot plugging and hot unplugging
* Node Health Check Operator
* SR-IOV Operator
* PCI passthrough
* {VirtProductName} cluster checkup framework
* {VirtProductName} on a cluster installed in FIPS mode
* IPv6
* {ibm-name} Storage scale
* {hcp-capital} for {VirtProductName}
* VM pages using HugePages
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The following features are not applicable on `s390x` architecture:
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* virtual Trusted Platform Module (vTPM) devices
* UEFI mode for VMs
* USB host passthrough
* Configuring virtual GPUs
* Creating and managing Windows VMs
* Hyper-V

Functionality differences::
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The following features are available for use on s390x architecture but function differently or require procedural changes:
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* When deleting a virtual machine by using the web console, the *grace period* option is ignored. For more information, see "Deleting a virtual machine by using the web console" in the Additional resources section.
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* When configuring the default CPU model, the `spec.virtualization.virtualMachineOptions.defaultCPUModel` value is `"gen15b"` for an {ibm-z-title} cluster. For more information, see "Configuring the default CPU model" in the Additional resources section.
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* When configuring a downward metrics device, if you use a VM preference, the `spec.preference.name` value must be set to `rhel.9.s390x` or another available preference with the format `*.s390x`. For more information, see "Configuring a downward metrics device" in the Additional resources section.
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* When creating virtual machines from instance types, you are not allowed to set `spec.domain.memory.maxGuest` because memory hot plugging is not supported on {ibm-z-name}. For more information, see "Creating virtual machines from instance types" in the Additional resources section.
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* Prometheus queries for VM guests could have inconsistent outcome in comparison to `x86`.
