Backups in a 24/7 world

Ninad Karpe talks about the backup and recovery challenges of maintaining a 24/7 enterprise, and suggests suitable strategies and solutions to achieve business objectives

Booming storage capacities and falling hardware costs are expanding the market for storage like never before. As storage becomes affordable, there is a bigger responsibility to protect data and make it available as and when it is needed.

Rapidly rising volumes of e-mail and other applications, accompanied by constant changes in hardware and software, have only aggravated this issue. Companies playing in global markets need to ensure that their storage processes are in sync with those of the rest of the world. For instance, current regulations specify the need for archiving important data or e-mail.

In a 24/7 environment, no organisation can afford destruction of data caused by virus attacks or even natural disasters. To keep data protected and available, a backup and recovery solution is necessary. While the desired levels of availability will vary depending on the needs of different organisations, every solution must be customisable and flexible according to an organisation’s needs and requirements.

Business challenges

In a 24/7 environment, organisations cannot afford periods of slow system response caused by traditional backup activities. The traditional method has been to backup the data on a server once a week and conduct an incremental backup on each of the other six days. This is not that easy anymore.

Massive growth in e-mail, databases, and other data has made organisations look at classifying their data depending on its importance to operations. For instance, lower cost solutions can be used as appropriate for less critical data. Every level of data can be given a different priority of protection and medium. Such a strategy enables organisations to efficiently spend resources and mitigate risks.

Let us take a look at the technologies available which can help organisations do this cost-effectively.

Online (Hot) backup and restore

Scheduling a backup during operations can cause slow system response. One way to avoid this is online or ‘hot’ backup. Online backup solutions back up the files when they are not in use and intelligently log open files so that they can be backed up later.

While this technique causes slower than normal access speeds, the advantage is that it allows data to be accessible even when it is backed up.

Disk to Disk (D2D) and Disk to Disk to Tape (D2D2T)

Both D2D and D2D2T involve using disk as the backup medium. In D2D2T, disk is used as an intermediate medium before it is offloaded to tape. Backups and restores can be done quickly and cost-effectively.

Snapshot-based backup and Restore

Just like a camera, this technology involves briefly freezing the data set and taking a quick snapshot of it. This snapshot can then be used as the backup copy which can then be backed up to another disk or tape device. The biggest benefit is that the backups and restores can be done at an extremely fast pace with no impact on operations.

Hardware-based snapshot

When a co-ordination between different applications (Exchange, SQL Server, Oracle) and the file and operating system needs to be achieved, a hardware-based snapshot is a preferred option over simple snapshot-based options. Hardware-based snapshot technology is provided by a disk array hardware vendor.

The interface used to generate hardware snapshots varies from vendor to vendor. Before choosing a hardware-based snapshot solution, CIOs have to ensure that the product seamlessly integrates with the application, operating system and the hardware snapshot technology of the disk array vendor. The key advantage is that backups can be done quickly and remotely with no impact on operations.

An integrated solution

While the above technologies have been available for a long time, the complexity— coupled with the hardware, software and administrative costs—has meant that these technologies have been adopted by only a small percentage of organisations.

While disk vendors have developed excellent hardware snapshot technology for their own arrays, the lack of co-ordination between different disk arrays, operating systems, backup and recovery solutions have meant that the potential of these technologies have not been fully utilised.

However, software vendors and leading disk array manufacturers are increasingly working together to create integrated solutions, thereby fully leveraging the capabilities of these solutions. Current technologies also make it possible for creating backups independent of the application server.

The author is the Managing Director of Computer Associates India