Chapter 1. Preparing to deploy OpenShift Container Storage using Red Hat Virtualization platform
Before you begin the deployment of Red Hat OpenShift Container Storage using dynamic or local storage, ensure that your resource requirements are met. See Planning your deployment.
Optional: If you want to enable cluster-wide encryption using an external Key Management System (KMS):
- Ensure that a policy with a token exists and the key value backend path in Vault is enabled. See Enabling key value backend path and policy in vault.
- Ensure that you are using signed certificates on your Vault servers.
Minimum starting node requirements [Technology Preview]
An OpenShift Container Storage cluster will be deployed with minimum configuration when the standard deployment resource requirement is not met. See Resource requirements section in Planning guide.
- Ensure that the requirements for installing OpenShift Container Storage using local storage devices are met.
1.1. Enabling key value backend path and policy in Vault
Prerequisites
- Administrator access to Vault.
-
Choose a unique path name as the backend
paththat follows the naming convention since it cannot be changed later.
Procedure
Enable the Key/Value (KV) backend path in Vault.
For Vault KV secret engine API, version 1:
$ vault secrets enable -path=ocs kv
For Vault KV secret engine API, version 2:
$ vault secrets enable -path=ocs kv-v2
Create a policy to restrict users to perform a write or delete operation on the secret using the following commands:
echo ' path "ocs/*" { capabilities = ["create", "read", "update", "delete", "list"] } path "sys/mounts" { capabilities = ["read"] }'| vault policy write ocs -Create a token matching the above policy:
$ vault token create -policy=ocs -format json
1.2. Requirements for installing OpenShift Container Storage using local storage devices
Node requirements
The cluster must consist of at least three OpenShift Container Platform worker nodes with locally attached-storage devices on each of them.
- Each of the three selected nodes must have at least one raw block device available to be used by OpenShift Container Storage.
- The devices you use must be empty; the disks must not include physical volumes (PVs), volume groups (VGs), or logical volumes (LVs) remaining on the disk.
For more information, see the Resource requirements section in the Planning guide.
Arbiter stretch cluster requirements [Technology Preview]
In this case, a single cluster is stretched across two zones with a third zone as the location for the arbiter. This is a technology preview feature that is currently intended for deployment in the OpenShift Container Platform on-premises.
For detailed requirements and instructions, see Configuring OpenShift Container Storage for Metro-DR stretch cluster.
You cannot enable both flexible scaling and arbiter as they have conflicting scaling logic. With flexing scaling, you can add one node at a time to the OpenShift Container Storage cluster. Whereas, in an arbiter cluster, you need to add at least one node in each of the 2 data zones.
Minimum starting node requirements [Technology Preview]
An OpenShift Container Storage cluster is deployed with minimum configuration when the standard deployment resource requirement is not met.
For more information, see Resource requirements section in the Planning guide.
