Overview
Storage Plug-in for Containers is a software component that contains libraries, settings, and commands that you can use to create a container in order to run your stateful applications. It enables the stateful applications to persist and maintain data after the life cycle of the container has ended. Storage Plug-in for Containers provides persistent volumes from Hitachi storage systems.
About Hitachi Storage Plug-in for Containers
Storage Plug-in for Containers integrates Kubernetes or OpenShift with Hitachi storage systems using Container Storage Interface (CSI).
The following diagram illustrates a container environment where Storage Plug-in for Containers is deployed.
The following table lists and describes the components of Storage Plug-in for Containers.
| Components of a containerized environment using Kubernetes and OpenShift CSI | |
| Component | Purpose |
| csi-controller | Implements the CSI controller service, which is mainly for storage operations. This is deployed as Deployment and runs only on a control plane. |
| csi-node | Implements the CSI node service, which primarily manages volumes on each node. This is deployed as DaemonSet, and all nodes must have this component. |
| Hitachi storage systems | Provides storage volumes for the containers. |
About the environment setup tasks
Storage Plug-in for Containers enables dynamic operation of storage systems when containers are used. In order to use Storage Plug-in for Containers pre-installation tasks must be completed.
Procedure
Check and apply the requirements for the server (where you plan to install Storage Plug-in for Containers, Kubernetes, and OpenShift),Hitachi storage systems, Kubernetes, and OpenShift.
Execute pre-installation tasks.
Set up the Kubernetes and OpenShift environment.
Configure the Hitachi storage systems.
Install Storage Plug-in for Containers.
Requirements
Before you install Storage Plug-in for Containers, check that your server and storage meet the following minimum requirements.
Server requirements
| Server requirements | |
| Component | Requirement |
| CPU | x86_64 |
| Operating system |
Refer to the release notes for details.
NoteYou can also use Red Hat Enterprise Linux CoreOS as a worker
node of OpenShift environments.
|
Storage requirements
Storage requirements for Virtual Storage Platform (VSP) family .
| Storage Requirements | |
| Component | Requirement |
| Model | Refer to the release notes for details. |
| SVOS | Refer to the release notes for details. |
| Interface | Fibre Channel and iSCSI for baremetal servers. iSCSI for vSphere virtual machines. |
| User account | The built-in Storage administrator (View & Modify) user group. If you are using a customized user group, make sure it has the same roles as the built-in Storage Administrator (View & Modify) user group. |
| License |
|
Storage requirements for Virtual Storage Software Block (VSSB).
| Component | Requirement |
| Version | Refer to the release notes for details. |
| Interface | Fibre Channel and iSCSI for baremetal servers. iSCSI for vSphere virtual machines. |
| User account | The user must have a Storage role. |
Pre-installation tasks
Before you install Storage Plug-in for Containers, review and apply the server and storage pre-installation requirements.
Server pre-installation
The following table outlines the pre-installation tasks for each server component.
| Server pre-installation tasks | ||
| Component | Tasks | |
| Hypervisor | If you want to use virtual machines, setup the hypervisor. NoteStorage Plug-in for Containers is tested with VMware vSphere 7.0. | |
| Fibre Channel | Verify if Fibre Channel HBA is installed on all hosts. | |
| iSCSI | Verify if iSCSI initiator software is installed on all hosts. If not, refer to: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/storage_administration_guide/osm-create-iscsi-initiator Note Storage Plug-in for Containers does not support the following items:
| |
| multipathd | Enable multipathd and ensure that the “user_friendly_names” option is set to yes: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/dm_multipath/mpio_setup | |
Storage pre-installation
Before installing, you must ensure that your environment meets the storage requirements. The following describes the pre-installation tasks to be completed for each storage component.
Storage pre-installation for VSP family
The following table outlines the pre-installation tasks to be completed for each storage component.
| Storage pre-installation tasks | |
| Component | Task |
| Program products |
|
| Pool |
|
| Fibre Channel connection | Use an Fibre Channel switch for communication between the storage and servers. Set the following parameters for storage ports by using Storage Navigator:
Host groups required for Storage Plug-in for Containers are automatically created by Storage Plug-in for Containers. If you want to use existing host groups, rename them according to the naming rule. For details, see Host group and iSCSI target naming rules). To the host group, add WWN for each host that joins the Kubernetes cluster. For example, if you have 10 hosts in your Kubernetes cluster, you must prepare 10 host groups. NoteStorage Plug-in for Containers will overwrite host mode options even if existing host groups have other host mode options. |
| iSCSI connection | Storage Plug-in for Containers automatically performs the following actions:
NoteStorage Plug-in for Containers will overwrite host mode options even if existing iSCSI targets have other host mode options. |
Host group and iSCSI target naming rules
Storage Plug-in for Containers automatically searches host groups and iSCSI targets based on the name.
If you want to use an already existing host group or iSCSI target, refer to either the naming rule of host groups or iSCSI targets depending on your storage connection:
Storage Plug-in for Containers searches host groups by the naming rule. If Storage Plug-in for Containers cannot find any host group in the port, it automatically creates the host group. If you already have host groups, you need to delete them or rename them according to the following naming rule:
"spc-<wwn1>-<wwn2>-<wwn3>"
Naming rule details:
- <wwn1>, <wwn2>, <wwn3> are the world wide name of each host.
- <wwn1>, <wwn2>, <wwn3> are sorted by name.
- If the host has more than three wwns, Storage Plug-in for Containers sorts <wwn1>, <wwn2> ... <wwnN> and uses lower three names.
- If the host has only one or two wwns, the names are "spc-<wwn1>" or "spc-<wwn1>-<wwn2>"
Storage Plug-in for Containers searches iSCSI targets by the naming rule. If Storage Plug-in for Containers cannot find any iSCSI target, it automatically creates the iSCSI target, "spc-<IQN>". If you already have iSCSI targets, you need to delete them or rename them according to the following naming rule:
“spc-<any string>”
Storage pre-installation for VSSB
| Component | Task |
| Fibre Channel connection | Use the Fibre Channel switch for communication between storage and servers. |
| Server resource | If you have already created a Server resource in VSSB, verify the following: Storage Plug-in for Containers automatically performs the following actions:
NoteDo not
add a WWN or IQN of multiple hosts to the same Server
resource. One Server resource can only be associated with a
single host. |