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Vendor Accent
Backup vs archiving
 Businesses
must realise that backup and archiving are two distinct processes, says Manish
Bapat.
Data centres are concerned with ever-increasing volumes of data. All data is
not active; there is inactive data that resides everywhere because of historical
transactions, use of data warehouses, and other reasons. Inactive data is not
accessed frequently and, therefore, it is less likely to be accessed. Some of
the reasons for maintaining inactive data are complying with regulations, anticipating
the need for future trend analysis and maintaining a history of customers.
Diverse requirements
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Archiving can improve performance.
By separating inactive data from active data, database scans and other
data access operations become faster
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Often used in the same context, backup and archiving are actually
two different processes, involving different capabilities often with competing
requirements. First and foremost, before companies consider different technologies
and the vendors available for each, they must distinguish between their backup
and archiving. Having a clear understanding of both these technologies and challenges
will help a business develop the foundation for an intelligent and robust storage
solution.
A typical backup application takes periodic images of active data to provide
a method of recovering records that have been accidentally deleted or destroyed.
Most backups are retained only for a few days or weeks as, later, backup images
supersede previous versions.
On the other hand, archiving requirements are different from those of backup.
Media longevity and data authenticity feature much more prominently in archiving
environments. The storage media used within an archive should be stable and
long lasting to avoid frequent data migration over decades of storage. To comply
with corporate and government regulations on data authenticity, it is crucial
that information is protected from modification. And that’s where archiving
comes into play.
Let’s look at some important aspects of each of these information management
technologies.
Archiving can result in two major benefits:
- It lets you reclaim disk space on the primary storage.
Saving disk space, along with other factors, can lower storage costs.
This also translates to a significant reduction in backup window and costs of
backup media.
- It can improve performance. By separating inactive data
from active data, database scans and other data access operations become faster.
E-mail archiving is usually an IT-driven purchase made because of the problems
that e-mail storage brings to the IT department. The performance of e-mail servers
can deteriorate exponentially when storing vast amounts of old e-mail, resulting
in users having to suffer e-mail quotas. With higher volumes year on year, e-mail
management is now a pressing IT problem that won’t go away.
Archiving reduces many of these storage problems, and some sophisticated versions
offer fast retrieval and other features. However, when those same systems are
employed as a compliance solution, the organisation is open to huge exposures
and liabilities.
| The essentials: Backup vs Archival |
| Backup
1. Backups are secondary
copiesof primary information. They provide short-term protection of production
data to ensure business continuity, are generated point-in-time and typically
in a periodic automated fashion, and are systematically overwritten.
2. Backup is done to provide a point-in-time copy
of information to protect critical business processes. Hence, backup solutions
are appropriate solutions for business continuity and disaster recovery.
3. The goal of a backup is data security through
redundancy plus ease in restoring your system and key files in case of
a calamity.
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Information archive
1. Information archives are the primary copies of
information. The characteristics of archived information are:
- It is valuable and retained for future reference. Its importance
means that information authenticity must be assured.
- It is typically in its final form, and subject to limited or no modification.
- As the sole copy of information, archived information must be retained
for longer periods (months, years or decades). Think of a thirty-year
mortgage, medical images, or product warranty information.
- Archives focus on access and retrieval of a specific piece of information
rather than all the content (a.k.a. backup).
- n Archival processes often include specific ILM time frames including
deletion.
2. Archives are performed regularly and the information
stored is maintained for long-term historical needs.
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The compliance framework
In the current business environment, no organisation is exempt from the government,
legal and regulatory pressures to store more data for longer periods. At the
same time, organisations are trying to do more with flat or falling IT budgets.
Today, information is growing at 60 to 70 percent while IT budgets are growing
at 3 to 4 percent. This situation is further worsened by the increasing number
of regulations such as Sarbanes-Oxley, BASEL II, HIPAA and SEBI Modified Clause
49 of Listing Agreement that are knocking at the doors of India Inc. While regulatory
compliance is fast catching up, many organisations are increasingly focussing
on corporate governance that essentially translates in compliance to the internal
set of policies and procedures. Therefore, organisations want archival storage
products that provide authenticity, long-term retention of data and low total
cost of ownership over time, without sacrificing the need for fast access and
reliability.
Increasing mandatory retention requirements also make demands on archiving systems
that they are often totally incapable of complying with; particularly when required
to. For example, demonstrating that data within the archive could not have been
altered or deleted without leaving an evidence trail. A forensic record is a
complete record, so any system allowing alteration or deletion via ‘policy-based
storage’ or ‘user-decision’ falls short of the mandatory standards
required.
IT departments are, therefore, realising that they must directly involve the
legal, compliance, data protection, and HR departments before deploying solutions.
All organisations must ensure privacy and integrity of data.
Choosing the right technology
 Storing
company data on the network can be costly. Valuable storage space can be taken
up by data which is rarely—or unlikely to be—accessed, and should
the server go down, chances are that due to the sheer amount of information
that is required to be retrieved, data will take time to be restored. Businesses
are aware that any network downtime can have a direct impact on the company’s
bottom line.
But using the most recent backup tape as an offline storage solution isn’t
enough. Few people with basic IT skills will have either the patience or the
technical capability to locate and find any single specific piece of information
and are, therefore, likely to turn to an already over-stretched IT department
for assistance.
Archiving software on the other hand simplifies the data storage and retrieval
processes. Data archiving systems that encompass hierarchical storage management
offer a true solution to managing and storing data intelligently within a company.
The use of optical disk DVD-R, CD-R or WORM (Write Once Read
Many)-based storage media means that data cannot be erased or changed in any
way, making it the ideal choice for organisations that need to store information
for legal reasons. The disks can hold between 650 MB and 4.7 GB of data. But
library systems that automate the loading of the disks indicate that storage
capacity of an archival system can grow in line with the company’s requirements
to provide infinite capacity. Newer products and solutions based on technologies
such as Content Addressed Storage (CAS) are fast emerging in the market to address
issues with magneto-optical media such as robotic arm failures, access times,
technology obsolescence and scalability limitations.
| Archiving and backup guidelines |
- Define the database backup schedule (including
full and incremental backups) appropriately to provide the necessary
resources for recovery.
- Define the data to archive based on business
policies. Schedule routine archive processing as needed to keep databases
at a manageable size.
- Select appropriate storage media for archiving
based on the business value and access requirements for each type of
data.
- Update the backup process to include archived
data.
- Select the appropriate low-cost storage media
for database backups to ensure recovery and reuse.
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An archiving solution enables companies to take a tiered approach to their
data needs:
- Live data can be stored on hard disk and is, therefore,
readily accessible.
- Data that is infrequently accessed is stored in
an optical library or CAS-based archiving product.
- Data that is rarely accessed is stored offline,
but is still managed as part of the overall archiving solution.
Archiving data using optical or CAS media ensures that it is stored near online,
thus freeing up valuable disk space for ‘live’ working documents.
As well as taking the pressure off the server, storing information offline can
also ensure that it is protected, should the worst happen to the server or network.
If any specific piece of information needs to be retrieved, archiving software
will direct the user to where the information is being held, so that they can
retrieve it easily.
With so many organisations now re- evaluating
their storage or recovery plans, it is important for users not to
let themselves be rushed into purchasing the latest solutions. Instead,
they should take a step back and think about the reality of their
business needs now and in the future. Planning right from the start
will lay the foundations for a cost-effective, secure storage solution.
The author is Business Manager, NAS & CAS,
EMC India & SAARC.
He can be reached at bapat_manish@emc.com
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