ExplanationOracle Cloud Infrastructure File Storage service provides a durable, scalable, secure, enterprise-grade network file system. You can connect to a File Storage service filesystem 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).
Large Compute clusters of thousands of instances can use the File Storage service for high-performance shared storage. Storage provisioning is fully managed and automatic as your use scales from a single byte to exabytes without upfrontprovisioning.
The File Storage service supports the Network File System version 3.0 (NFSv3) protocol. The service supports the Network Lock Manager (NLM) protocol for file locking functionality.
Oracle Cloud Infrastructure File Storage employs 5-way replicated storage, located in different fault domains, to provide redundancy for resilient data protection. Data is protected with erasure encoding.
The File Storage service uses the "eventual overwrite" method of data eradication. Files are created in the filesystem with a unique encryption key. When you delete a single file, its associated encryption key is eradicated, making the file inaccessible. When you delete an entire file system, the file system is marked as inaccessible. The service systematically traverses deleted files and file systems, frees all the used space, and eradicates all residual files.
Use the File Storage service when your application or workload includes big data and analytics, media processing, or content management, and you require Portable Operating System Interface (POSIX)-compliant file system access semantics and concurrently accessible storage. The File Storage service is designed to meet the needs of applications and users that need an enterprise file system across a wide range ofuse cases, including the following:

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Disaster recovery (DR) involves a set of policies, tools and procedures to enable the recovery or continuation of vital technology infrastructure and systems. A disaster can be any event that puts your applications at risk, from network outages to equipment failures to natural disasters. A well architected disaster recovery (DR) plan enables you to recover quickly from disasters and continue to provide services to your users. Oracle Cloud Infrastructure provides highly available, secure, and scalable infrastructure and services that enable you recover your cloud workloads quickly, reliably, and securely.
> DR Concepts: The first step in planning for DR involves determining the recovery time objective (RTO) and recovery point objective (RPO). The RTO is the target time within which a given application must be restored after a disaster occurs. Typically, the more critical the applications, the lower the RTO. The RPO is the period after a disaster occurs for which the application can tolerate lost data before the disaster begins to affect the business. To build a plan that guarantees the recovery of your applications after a disaster and is cost effective, you must consider both the target time to recover and the tolerance for data loss. > Disaster Scenarios: Planning for DR requires a thorough understanding of all the possible scenarios that can cause disasters. > Application Failure: An application can fail Network Failure of failures in the underlying infrastructure or issues related to changes in software or hardware configuration. It's important to include monitoring capability in your DR solution design so that application failures are detected and alerts are sent. Depending on your requirements, your DR solution can range from simply backing up application data and configurations to a fully active-to-active failover setup that seamlessly mitigates many types of failures. > Network Failure: For DR, consider potential network outages in your cloud environment. For example, if you use an IPSec VPN connection to connect your on-premise data centers to Oracle Cloud, the IPSec VPN connection could experience network performance or outage issues. We recommend setting up multiple IPSec VPN connections or using both FastConnect and IPSec VPN connections so that you have sufficient redundancy for your network connections. Data Center Failure An unexpected event could affect an entire data center (availability domain). In your DR solution design, plan for this kind of failure. If your region has multiple availability domains, we recommend deploying your applications across the availability domains to accommodate potential issues for a particular data center. If your region has only one availability domain, consider a combination of multiple fault domains and multiple-region configurations, as defined in the recommendations for a region failure. > Region Failure: A natural disaster could cause an entire Oracle Cloud Infrastructure region to be out of service. This scenario could be one of the most severe cases in your DR design. To protect against this scenario, deploy your workloads across multiple Oracle Cloud Infrastructure regions. Depending on your DR goals (RTO and RPO), you can back up or replicate your data to another region, or set up a fully active-to-active standby in another region.

You are billed for the dedicated virtual machine host as soon as you create it, but you are not billed for any of the individual VM instances you place on it. You will still be billed for image licensing costs if they apply to the image you are using for the VM instances.