Considerations for Storage

To understand the Oracle Cloud Infrastructure storage options, it's important to define the following storage characteristics: performance, durability, availability, scalability, elasticity, security, and access method.

Performance describes the combination of throughput, bandwidth, and latency.
Durability ensures that the data is saved and not susceptible to loss or erasure during a crash.
Availability of the service describes how the storage service is built within the availability domains to ensure access to the data.
Scalability and elasticity describe how easy it is to grow or shrink data while being able to move the data between compute systems.
Security describes how data is secured from unauthorized access.
Access method describes how customers can access data across the different storage offerings.

Use the following matrix to help you determine which data storage option to use to ensure a successful application migration to Oracle Cloud Infrastructure. More information about each option is provided in sections following the matrix.

Storage Characteristics	File	Block	NVMe	Object	Archive
Performance	Good	Better	Best	Good	Cold Line
Durability	Across availability domains	Across availability domains	Locally Managed	Regional	Across regions
Availability	High	High	Locally Managed	High	Persistent
Scalability	High	High	Static	High	High
Elasticity	Automatic	Dynamic	Static	Automatic	Automatic
Security	Shared	Shared	Individual Host	Shared	Shared
Access Method	Network	Dedicated	Direct	HTTPS	HTTPS

File Storage

The Oracle Cloud Infrastructure File Storage service supports the Network File System version 3.0 (NFSv3) protocol. You can connect to a File Storage service file system from any bare metal, virtual machine, or container instance in your Virtual Cloud Network (VCN). You can also access a file system from outside the VCN using Oracle Cloud Infrastructure FastConnect and Internet Protocol security (IPSec) virtual private network (VPN).

The FileStorage service is designed to meet the needs of applications and users that need an enterprise file system across a wide range of use cases, including the following:

General Purpose FileStorage: Access to an unlimited pool of file systems to manage growth of structured and unstructured data.
Big Data and Analytics: Run analytic workloads and use shared file systems to store persistent data.
Lift and Shift of Enterprise Applications: Migrate existing Oracle applications that need NFS storage, such as Oracle E-Business Suite and PeopleSoft.
Databases and Transactional Applications: Run test and development workloads with Oracle, MySQL, or other databases.
Backups, Business Continuity, and Disaster Recovery: Host a secondary copy of relevant file systems from on-premises to the cloud for backup and disaster recovery purposes.
MicroServices and Docker: Deliver stateful persistence for containers. Easily scale as your container-based environments grow.

If NFS files are used in the on-premises data center, then moving to File Storage can be simple and direct. If there is a reliance on Microsoft Windows Server, use the NFS client to attach the NFS shares to the Windows Server hosts.

Block Volume

The Oracle Cloud Infrastructure Block Volumes service lets you expand your current storage footprint. It provides persistent storage that can move between instances within Oracle Cloud Infrastructure. Volumes work with both bare metal and virtual machine (VM) instances, and they are attached via iSCSI for data volumes or paravirtualized

Block Volume lets an Oracle Cloud Infrastructure user create, attach, connect, and move volumes as needed to meet application storage requirements. After you attach a volume to an instance, the volume behaves like a standard hard drive. Volumes can also be disconnected and attached to another instance without the loss of data, thus allowing for easy moment of data between instances as requirements change.

The following components are required to create a volume and attach it to an instance:

Instance: A bare metal or VM host running in the cloud.
Volume attachment: One of the following types:
- iSCSI: A TCP/IP-based standard used for communication between a volume and attached instance.
- Paravirtualized: A virtualized attachment available for VMs.
Volume: One of the following types:
- Block volume: A detachable block storage device that lets you dynamically expand the storage capacity of an instance.
- Boot volume: A detachable boot volume device that contains the image used to boot a Compute instance.

Block Volume supports policy-based backups, with predefined policies of Bronze (monthly), Silver(weekly), and Gold (daily). These policies let you customize full and incremental backups, and give you a five-year backup retention for full backups.

Block volumes on Oracle Cloud Infrastructure are a great performance option and provide flexible configuration for HDFS capacity. Block volumes are a network attached storage, and as such they use VNIC bandwidth for I/O. Block volumes also scale in IOPS and MB/s based on their configured size (per GB). Individual block volume throughput maxes out at 320 MB/s for 700GB or larger volumes.

NVMe Devices

Oracle Cloud Infrastructure provides locally attached NVMe devices in some specific compute shapes. These devices provide extremely low-latency, high-performance block storage that is ideal for big data, OLTP, and any other workload that can benefit from high-performance block storage.

Note that these devices are not protected in any way; they are individual devices locally installed on your instance. Oracle Cloud Infrastructure does not take images, back up, or use RAID or any other methods to protect the data on NVMe devices. These devices are not automatically protected and require the proper RAID configuration to protect the data on them.

Object Storage

Use Oracle Cloud Infrastructure Object Storage for data to which you need fast, immediate, and frequent access. Data accessibility and performance justifies a higher price point to store data in the Object Storage tier.

The Object Storage service can store an unlimited amount of unstructured data of any content type, including analytic data and rich content, like images and videos.

With Object Storage, you can safely and securely store or retrieve data directly from the internet or from within the cloud platform. Object Storage is a regional service and is not tied to any specific compute instance. You can access data from anywhere inside or outside the context of the Oracle Cloud Infrastructure, as long you have internet connectivity and can access one of the Object Storage endpoints. Object Storage also supports private access from Oracle Cloud Infrastructure resources in a VCN through a service gateway. A service gateway allows connectivity to the Object Storage public endpoints from private IP addresses in private subnets.

The following list summarizes some of the ways that you can use Object Storage.

Hadoop/Big Data Support - You can use Object Storage as the primary data repository for big data. Object Storage offers a scalable storage platform that lets you store large datasets and operate seamlessly on those datasets.
Backup/Archive - You can use Object Storage to preserve backup and archive data that must be stored for an extended duration to adhere to various compliance mandates.
Content Repository - You can use Object Storage as your primary content repository for data, images, logs, and video.
Log Data - You can use Object Storage to preserve application log data so that you can retroactively analyze this data to determine usage pattern and debug issues.
Large Datasets - You can use Object Storage to store generated application data that needs to be preserved for future use. Pharmaceutical trials data, genome data, and Internet of Things (IoT) data are examples of generated application data that you can preserve using Object Storage.

Archive Storage

Use Archive Storage for data to which you seldom or rarely access, but that must be retained and preserved for long periods of time. The cost efficiency of the Archive Storage tier offsets the long lead time required to access the data.

Archive Storage is ideal for storing data that is accessed infrequently and requires long retention periods. ArchiveStorage is more cost effective than Object Storage for preserving cold data for:

Compliance and audit mandates
Retroactively analyzing log data to determine usage pattern or debug problems
Historical or infrequently accessed content repository data
Application-generated data requiring archival for future analysis or legal purposes

Unlike Object Storage, Archive Storage data retrieval is not instantaneous.