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

= Limitations for adopting the {block_storage}

Before you begin the {block_storage_first_ref} adoption, review the following limitations:

* There is no global `nodeSelector` option for all {block_storage} volumes. You must specify the `nodeSelector` for each back end.
* There are no global `customServiceConfig` or `customServiceConfigSecrets` options for all {block_storage} volumes. You must specify these options for each back end.
* Support for {block_storage} back ends that require kernel modules that are not included in Red Hat Enterprise Linux is not tested in {rhos_long}.
