Using NAS to simplify backups

To all companies, data is a vital resource for business operations. Protecting data from corruption, user error, hardware failure, theft or site disaster is widely recognized to be a critical requirement for information systems and data management.

For decades, tape-based backup and restore technologies have been the primary mechanisms for protecting data from corruption or loss, and they continue to be the best methods for archiving data. However, managing many server-based tape backups in a LAN can become a problem as small and medium-size businesses grow. With each additional server brought online to increase storage and production capacity, an additional tape drive must be directly attached to provide backup protection, which drives up equipment costs and overwhelms server administrator resources.

Is there a less-expensive way to simplify management and improve backup operations? Yes. Network-attached storage (NAS) delivers a more efficient and effective way to protect data by providing a network-based centralized backup model. The NAS controls the backup processes of all the clients and servers providing centralized disk and tape storage. This centralized networked approach reduces the amount of equipment required for backup operations and, in turn, lowers the management costs of backup administration.

Network-attached storage is the best choice for backup operations in the following three scenarios:

  • Client backups.

  • Server backups.

  • Remote replication.

In all of these scenarios, backups are performed over a LAN, WAN or virtual private network (VPN). In most cases, customers will want to leverage the tape backup systems already in place, so they should look for NAS systems based on standards that integrate easily into their existing infrastructure, such as those powered by Microsoft Corp.'s storage operating system. From a software perspective, backup "engine" software must be loaded onto the NAS to control the backup process, and onto the data source "host" (e.g., a desktop PC or a notebook) to push data to the backup engine. Most NAS vendors offer backup software solutions from companies such as Veritas Software Corp. integrated into their NAS systems.

NAS for Client Backups

Russ Holt

Because of heavy daytime use, companies usually schedule desktop and workstation backups after hours, when user activity is light. In contrast, because notebooks and handheld devices are frequently used remotely, they must be backed up during the day when they are docked at the work site. In addition, most notebooks aren't configured for tape backups. Different client agents are required for desktops and mobile devices. The following are the processes for performing the backups in those scenarios:

  • Desktops and Workstations

    1. Load client agent software on each desktop or workstation.
    2. Schedule the NAS to back up data sources after hours.
    3. Data is transmitted over the LAN to the NAS, which controls the tape device for sequential backups of each desktop and workstation (disk to tape).
  • Notebooks and Mobile Devices

    1. Load mobile backup software on each notebook or mobile device.
    2. After the mobile device is docked, the NAS initiates transfer of data across the network to storage on the NAS (disk to disk).
    3. The NAS backs up the data to tape.

NAS for Server Backups

Specialized software is required to back up multiple networked servers across different platforms. For businesses that operate 24/7, this software provides point-in-time copies of data, commonly referred to as "snapshots." The following is the process to follow for using NAS in server backups:

  1. Load the backup software agent on each application server.
  2. Backups are scheduled by the server administrator and are completed without application downtime.
  3. Snapshots are transferred across the network to the NAS.
  4. Snapshots can be stored on the NAS for fast recovery (disk to disk).
  5. Snapshots can be backed up from the NAS to the tape device for archival or off-site storage.

NAS for Remote Site Replication and Central Backup

Organizations with remote or branch offices can use network-attached storage and remote site replication technology to provide a centralized disaster recovery solution. This is the process they should follow:

  1. Load replication software on each remote site's NAS and on the central NAS backup system.
  2. Data from each remote NAS is transmitted synchronously or asynchronously across the network to the central backup NAS (disk to disk).
  3. The central NAS controls the backups to a tape device (disk to tape).

In these three backup scenarios, NAS offers distinct benefits over older backup technologies, including the following:

  • Consolidation of backup equipment: With storage attached to the network rather than directly to the server, it's no longer necessary to attach a tape device to each server for backups. Tape equipment can be consolidated directly onto NAS systems, reducing labor costs associated with maintaining multiple tape devices. This allows businesses to invest in a smaller number of high-quality tape devices (e.g., tape autoloaders or libraries) and to maintain them in environments controlled for temperature and humidity.

  • Streamlined backup management: Using the NAS to control the backup and restore processes simplifies management by centralizing backup operations. Server administrators save valuable time since they no longer have to go to each individual machine to execute backups. Using a Web-based interface, administrators can schedule a NAS system to back up all servers to tape, eliminating any data conflicts between servers.

  • Effective management of backup Windows: All backups are scheduled and controlled through the NAS. Data is backed up from the NAS to tape when network traffic is minimal.

  • Reduced backup time: Disk-to-disk backups with a NAS are faster than disk to tape, reducing the backup window time. When backed-up data must be frequently accessed, disk-to-disk restores are much less time consuming than restores from tape.

As businesses grow, the amount of data that requires storage and protection will increase dramatically. At the same time, the window of time during which data can be backed up without having a negative impact on business operations has decreased. These factors make the server administrator's job of storing and protecting data fundamentally more challenging. Incorporating NAS into backup operations streamlines management operations, lowers the total cost of ownership and offers an additional backup solution in the form of disk-to-disk backups.

Copyright © 2003 IDG Communications, Inc.

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