Backups in a 24/7 world
Karpe talks about the backup and recovery challenges of maintaining a 24/7
enterprise, and suggests suitable strategies and solutions to achieve business
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
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 organisations needs
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
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.
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.
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.
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
An integrated solution
While the above technologies have been available for a long time, the complexity
coupled with the hardware, software and administrative costshas 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