:_mod-docs-content-type: CONCEPT
[id="adoption-limitations_{context}"]

= Adoption limitations

Before you proceed with the adoption, check which features are Technology Previews or unsupported.

.Technology Preview

The following features are Technology Previews and have not been tested within the context of the {rhos_long_noacro} adoption:

* NFS Ganesha back end for {rhos_component_storage_file_first_ref}
* iSCSI and FC-based drivers for {block_storage_first_ref}
* {block_storage} back end for the {image_service_first_ref}

The following {compute_service_first_ref} features are Technology Previews:

* Compute hosts with `/var/lib/nova/instances` on NFS
* NUMA-aware vswitches
* PCI passthrough by flavor
* SR-IOV trusted virtual functions
* vGPU
* Emulated virtual Trusted Platform Module (vTPM)
* UEFI
* AMD SEV
* Direct download from Rados Block Device (RBD)
* File-backed memory
* Defining a custom inventory of resources in a YAML file, `provider.yaml`

.Unsupported features

The adoption process does not support the following features:

* instanceHA
* DCN
* Designate
* {loadbalancer_first_ref}
* BGP
* Adopting a FIPS environment
* The {key_manager} only supports the simple crypto plug-in


//* When you adopt a {OpenStackShort} {rhos_prev_ver} FIPS environment to {rhos_acro} {rhos_curr_ver}, your adopted cluster remains a FIPS cluster. There is no option to change the FIPS status during adoption. If your cluster is FIPS-enabled, you must deploy a FIPS {rhocp_long} cluster to adopt your {OpenStackShort} {rhos_prev_ver} FIPS control plane. For more information about enabling FIPS in {OpenShiftShort}, see link:{defaultOCPURL}/installing/installation-overview#installing-fips[Support for FIPS cryptography] in the {OpenShiftShort} _Installing_ guide.