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Configuration: Premium Feature— Snapshot Virtual Disks

NOTE: If you ordered this feature, you received a Premium Feature Activation card shipped in the same box as your Dell PowerVault MD storage array. Follow the directions on the card to obtain a key file and to enable the feature.

NOTE: The snapshot feature allows up to eight snapshots per LUN and 128 per array to be present at the same time.

A snapshot virtual disk is a point-in-time image of a virtual disk in a storage array. It is not an actual virtual disk containing a copy of the original data; It is a reference to the data that was contained on a virtual disk at a specific time. A snapshot virtual disk is the logical equivalent of a complete physical copy. However, you can create a snapshot virtual disk much faster than a physical copy, using less disk space.

The virtual disk on which the snapshot is based, called the source virtual disk, must be a standard virtual disk in your storage array. Typically, you create a snapshot so that an application, such as a backup application, can access the snapshot and read the data while the source virtual disk remains online and accessible.

NOTE: No I/O requests are permitted on the source virtual disk while the virtual disk snapshot is being created.

Asnapshot repository virtual disk containing metadata and copy-on-write data is automatically created when a snapshot virtual disk is created. The only data stored in the snapshot repository virtual disk is that which has changed since the time of the snapshot.

After the snapshot repository virtual disk is created, I/O write requests to the source virtual disk resume. Before a data block on the source virtual disk is modified, the contents of the block to be modified are copied to the snapshot repository virtual disk for safekeeping. Because the snapshot repository virtual disk stores copies of the original data in those data blocks, further changes to those data blocks write only to the source virtual disk. The snapshot

Configuration: Premium Feature—Snapshot Virtual Disks

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MD3200i, MD3220i specifications

The Dell MD3220i and MD3200i are part of Dell's extensive line of modular storage solutions, designed to support organizations in optimizing their data management and scalability requirements. These models offer reliable performance and flexible features, making them suitable for various workloads including virtualization, cloud storage, and disaster recovery.

One of the standout features of the MD3220i and MD3200i is their support for iSCSI storage networking. By utilizing the Internet Small Computer Systems Interface (iSCSI) protocol, these systems provide organizations with a cost-effective way to connect their storage over existing network infrastructure, enabling efficient data transfers and management.

Both models are equipped with dual controllers that ensure high availability and failover capabilities, which are crucial for meeting uptime requirements in mission-critical environments. The dual controllers also facilitate load balancing and increase overall system performance, as they allow multiple paths to the storage, enhancing I/O performance.

Scalability is another key characteristic of the MD3220i and MD3200i. These storage arrays can be expanded to meet growing storage demands, supporting up to 240TB of raw capacity with up to 16 additional expansion enclosures. This flexibility allows organizations to start with a smaller configuration and grow their storage capabilities without a complete overhaul of the existing infrastructure.

The units also support multiple disk types, including traditional spinning disks, solid-state drives (SSDs), and a combination of both. This versatility enables users to tailor storage configurations to their specific performance and budgetary needs. Furthermore, the systems feature advanced data management technologies such as snapshots and remote replication, providing essential tools for data protection.

With their ease of management, the MD3220i and MD3200i are designed for straightforward configuration and operation. The intuitive management interfaces allow IT professionals to monitor performance, configure storage, and manage data effectively, ensuring businesses can maintain optimal system availability.

In summary, the Dell MD3220i and MD3200i are robust, scalable, and versatile storage solutions that cater to diverse organizational needs. Their integrated technologies, such as iSCSI support, dual controller architecture, and advanced data management features, make them an ideal choice for modern data centers looking to enhance storage capabilities while ensuring reliability and performance.