Chapter 6. Red Hat Storage Volumes

A Red Hat Storage volume is a logical collection of bricks, where each brick is an export directory on a server in the trusted storage pool. Most of the Red Hat Storage Server management operations are performed on the volume. For a detailed information about configuring Red Hat Storage for enhancing performance see, Chapter 9, Configuring Red Hat Storage for Enhancing Performance

Warning

Red Hat does not support writing data directly into the bricks. Read and write data only through the Native Client, or through NFS or SMB mounts.

Note

Red Hat Storage supports IP over Infiniband (IPoIB). Install Infiniband packages on all Red Hat Storage servers and clients to support this feature. Run the yum groupinstall "Infiniband Support" to install Infiniband packages.

Volume Types

Distributed
Distributes files across bricks in the volume.
Use this volume type where scaling and redundancy requirements are not important, or provided by other hardware or software layers.
See Section 6.3, “Creating Distributed Volumes” for additional information about this volume type.
Replicated
Replicates files across bricks in the volume.
Use this volume type in environments where high-availability and high-reliability are critical.
See Section 6.4, “Creating Replicated Volumes” for additional information about this volume type.
Distributed Replicated
Distributes files across replicated bricks in the volume.
Use this volume type in environments where high-reliability and scalability are critical. This volume type offers improved read performance in most environments.
See Section 6.5, “Creating Distributed Replicated Volumes” for additional information about this volume type.

Important

Striped, Striped-Replicated, Distributed-Striped, and Distributed-Striped-Replicated volume types are under technology preview. Technology Preview features are not fully supported under Red Hat subscription level agreements (SLAs), may not be functionally complete, and are not intended for production use. However, these features provide early access to upcoming product innovations, enabling customers to test functionality and provide feedback during the development process.

Striped
Stripes data across bricks in the volume.
Use this volume type only in high-concurrency environments where accessing very large files is required.
See Section 6.6, “Creating Striped Volumes” for additional information about this volume type.
Striped Replicated
Stripes data across replicated bricks in the trusted storage pool.
Use this volume type only in highly-concurrent environments, where there is parallel access to very large files, and performance is critical.
This volume type is supported for Map Reduce workloads only. See Section 6.8, “Creating Striped Replicated Volumes” for additional information about this volume type, and restriction.
Distributed Striped
Stripes data across two or more nodes in the trusted storage pool.
Use this volume type where storage must be scalable, and in high-concurrency environments where accessing very large files is critical.
See Section 6.7, “Creating Distributed Striped Volumes” for additional information about this volume type.
Distributed Striped Replicated
Distributes striped data across replicated bricks in the trusted storage pool.
Use this volume type only in highly-concurrent environments where performance, and parallel access to very large files is critical.
This volume type is supported for Map Reduce workloads only. See Section 6.9, “Creating Distributed Striped Replicated Volumes” for additional information about this volume type.

6.1. About Encrypted Disk

Red Hat Storage provides the ability to create bricks on encrypted devices to restrict data access. Encrypted bricks can be used to create Red Hat Storage volumes.
For information on creating encrypted disk, refer to the Disk Encryption Appendix of the Red Hat Enterprise Linux 6 Installation Guide.