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Filling the Gap in Backup Protection
Adobe Acrobat Version
Since the beginning of the computing age, it has been universally understood that backup is a critical
element in protecting against data loss. With the mountains of data being entered in today's online
environment, the ability to recover lost data is not a luxury, but a fundamental part of doing business.
Bare Metal Recovery (BMR) is most often considered a supplemental layer of protection that can help
insulate an organization against unnecessary downtime. While file-by-file backup and restore software is
excellent at protecting against data loss, there is an inherent disadvantage in being able to quickly
return an unbootable machine to a fully operational state. The shortcomings are the many steps required to
perform a file-by-file recovery, and the lack of guarantee that every operating system (OS) change has been
reinstated even after a restore. Thus, BMR should actually be a vital part of any company's disaster
recovery plan, not just an afterthought.
THE HISTORY OF BARE METAL RECOVERY
In the early days, the cost of storage was so high that individual transactions were printed on punch
cards, paper tape, or ledger cards. Customer transaction totals were stored on a magnetic stripe on the
back of a ledger card, tape cassette, or, for those who could afford big iron, disk. Because of the high
expense for tiny amounts of storage, and since hardware frequently failed, systems were designed to allow
companies to limp along using paper as a fall back during what were often long repair periods.
As technical advances in storage brought the cost per byte down, more data could be kept online. This
meant that backup vendors had to keep pace by creating better technology. In some cases advancements were a
requirement, and not just produced out of a desire to invent the next big thing. A good example of a
necessary development was bare metal disaster recovery.
BMR was a mandatory function for Digital Equipment Corporation VAX users, back when DEC was a major
player in the minicomputer market. This was because a VAX only supported one OS. Computers from other
manufacturers often supported multiple OS drives so, if one failed (for any reason), you could simply boot
from another drive. BMR was a technology born of a requirement by VAX end users to quickly and easily
restore a "dead" machine that had lost its ability to boot. This is also often referred to as "cold" booting
a machine.
When Microsoft developed Windows NT, they too designed a machine that only supported one OS drive.
Windows end users had the same problem as VAX users – it was no easy task to re-install an OS and get a
machine restored to the same point it was before an unbootable type of failure. It wasn't long before VAX
users, who had converted to Windows NT, started asking for a BMR equivalent.
The third party software community that specializes in backup was slow to understand the significance of
BMR. For many users, an OS failure had never been a large issue for the equipment they supported before
moving over to NT. However, as more sophisticated end users moved to the new OS, demand for a method to
quickly and easily restore a failed machine gained momentum. In order to create this solution, vendors were
required to think beyond the traditional file-by-file backup and restore methods that were so prevalent up
until just a few years ago. Therefore, the BMR products available in today's market have been greatly
influenced by the success of Windows in the business environment.
Over the past five years there has been an explosion of new hardware and software options for end users
that offer better protection. Due to the amount of choices available, it is not surprising many end users
are unsure as to which data protection approaches are critical and should be funded, versus what might be
optional for their unique environment. Computer downtime is a leading contributor to overall business
failure so it is prudent to minimize this risk. However, a major problem is balancing a viable solution
cost against acceptable levels of downtime since it is extremely costly to buy and implement a non-stop
computing system.
THE WINDOWS NT ERA
When Microsoft released Windows NT, nearly the entire user population regularly backed up to tape using
the built-in backup product. As third party backup solutions began to emerge, UltraBac Software introduced
the first Windows server backup product that not only backed up to tape, but was actually designed to write
to disk as a storage option. As the price of disk storage continued to fall in the late 1990's, every
competitive backup product in the Windows market released some type of disk-to-disk functionality. Consumer
demand had inspired this move to a different and more stable form of backup media, as tape had often proved
to be less than completely reliable. These requests for alternate storage only accelerated as the price of
disks continued to fall.
As end users became more reliant on the faster disk-to-disk backups, they realized there was a huge hole
in their file-by-file restores. The ability to back up to disk more rapidly than tape created the
expectation of faster restores. However, with traditional restore methods this was not possible. When it
took five hours to back up to tape, recovering a failed machine in five hours as well was considered normal
if not outstanding. When backup times were cut in half, the technology to restore a totally failed machine
in a timely manner had to be created.
Once Windows NT was released, customers frequently experienced what was labeled "The Blue Screen of
Death." A blue screen event normally did not cause any data loss; the machine just became unbootable and
therefore was unusable until recovered. To recover, an administrator had to install a temporary operating
system, install the backup software, use the backup software to restore the operating system partition, and
then reboot. Backup and restore was almost always performed to and from tape with a common problem – a
restored backup often did not have key information that had been layered on the machine since installation.
Aside from how long a restore took, the fact that a failed machine typically was not completely restored to
the full status at which it failed, initiated the demand for a better way to recover. This led to the
development of BMR for Windows. Unfortunately, many end users initially resisted investing in this software
technology because of perceived lack of functionality and high cost assumptions.
TIME IS MONEY
While the definition (and monetary value) of a timely recovery of a failed machine can vary from
organization to organization, one unarguable fact is that downtime costs money. Actual system downtime loss
is an expense that is usually not well perceived in most organizations – it can even vary by the time of
day. Downtime for Company A might cost $5,000 an hour while the cost for Company B could be $100,000 an
hour. Even the rate between individual servers within a company can be vastly different depending on the
critical nature of the applications being run. Here is a very simple formula to estimate downtime:
(Employee costs per hour) x
(Fraction of employees affected by outage + Average income per hour) x
(Fraction of income affected by outage)
= Estimated average cost of one hour of downtime
*A Simple Way to Estimate the Cost of Downtime – David A. Patterson, Computer Science Division, UC Berkeley
Downtime costs fall into two broad categories: tangible and intangible. Calculating tangible costs such
as employee wages, operating costs, and office expenses are straight forward and can be estimated with
great accuracy using a simple formula like the one provided above. The difficultly lies in factoring all of
the potential intangible costs such as lowered employee morale, missed opportunities, forgone sales, and
loss of customer goodwill. These are hard to assign accurate costs. The bottom line is all companies
recognize computer downtime means lost money. Regrettably, most don't realize how much it truly costs.
DECREASING RESTORE TIMES – INCREASING AVAILABILITY
Organizations can significantly decrease server downtime by implementing a quality bare metal recovery
solution. Standard file-by-file recovery methods simply cannot bring a server back online quickly or easily.
BMR software offers an economical way to eliminate unnecessary downtime, making machine failures less
expensive. In some cases, the first use of a BMR solution can provide the user their full return on
investment.
There are many expensive hardware and software products on the market that are designed to offer non-stop
computing. They do a fine job, but do not eliminate or even help with unbootable events. For example, no
matter the quality of a RAID device, or how reliable a cluster server or replication product, none of these
can help overcome installing a bad driver that causes a blue screen. In a situation such as this,
replication software simply becomes 'double trouble' because the bad driver is replicated to the fail-over
machine, making it unbootable as well.
DEFINING BARE METAL RECOVERY
Bare metal recovery is essentially the process of taking a low-level snapshot of a machine's operating
system partition and storing it where it can be quickly and easily accessed when required. A BMR solution
has two parts. The first is a program that is set up to periodically snapshot an OS partition using image
backup technology. This is installed as a service and comes with a scheduler. The scheduler is then
programmed to take backups of the live machine without any requirement to shut down services, close
applications, or go offline. Image backups are normally stored to a UNC path, SAN, or NAS device for online
storage and quick access when needed.
The second part of a BMR solution is the process used to boot a dead machine. This enables users to
connect to the online location where the image backups have been stored and initiate a restore. Once the OS
partition has been restored (which can take between 5 to 30 minutes), the only remaining steps necessary
to complete the disaster recovery are to remove the boot media and reboot the machine. This latter phase
takes approximately two minutes before the machine is back to the exact state at which the image backup was
performed.
Static image backups are typically performed every 24 hours, with options for incremental and
differential backups between full backups. The newest functionality for BMR is continuous image protection,
or CIP. CIP can also be referred to as CDP, or continuous data protection, but the term CDP does not
differentiate between block or file protection. Many CDP products on the market today only provide
continuous data protection for applications such as SQL or Exchange, whereas CIP offers comprehensive
protection for all applications on a disk. The advantage both CDP and CIP do offer is the ability to
restore a machine to a closer point-in-time to the actual root cause of an unbootable failure, as opposed
to a standard image backup that might be 23 hours old.
Using regular file-by-file backup software, restoring a failed server takes most organizations anywhere
between two hours to two days to accomplish. By implementing a BMR solution, restoring the same OS partition
that took hours using a regular file-based restore might be accomplished in under 10 minutes. Not only is
BMR fast, but it is simple when compared to a file-based restore. A sophisticated BMR product can also be
fully scripted – even a security guard on the night shift could recover a strategic 24x7 server.
WHAT TO LOOK FOR IN A BMR SOLUTION
When image-based disaster recovery first appeared in the Windows environment, the majority of users were
astonished at how fast and simple recovering failed servers became. Unfortunately, certain restrictions
applied. In order to restore the saved backup image files, they were required to be restored to the same or
nearly identical hardware. As BMR software has evolved, key features were introduced to make this solution
truly flexible.
The technology has become an integral disaster recovery application for more and more enterprise level
businesses, and now the SMB market is realizing that it is as vital to them as it is for larger companies.
When considering which software application is right for a company, here are some key features to look for
in a bare metal recovery solution:
- Dissimilar hardware restore
- Virtual consolidations and disaster recovery
- Restore to larger partitions and disks
- Restore to smaller partitions and disks
- The ability to safely restore Active Directory and Domain Controllers
- Full, incremental, and differential options
- Continuous image protection (CIP)
- Fully scripted backups and restores
- Remote management
- Backup and restore using FTP/SFTP
- Backup and restore using IBM Tivoli Storage Manager
- Backup and restore using any local or remote tape drive
- Backup and restore using any local or remote library
- Backup and restore using any local disk, UNC path, SAN, NAS, USB, or FireWire device
- Backup and restore using CD, DVD, USB Key, or PXE/RIS
- Backup and restore through tightly locked down firewalls
- Disk-to-disk-to-tape options for redundant and off-site storage
HOW BMR SAVES MONEY
Every minute of machine downtime costs an organization time and money. Therefore, everyone should be able
to agree that limiting downtime is highly desirable, particularly if it is reasonably affordable. To
demonstrate the return on investment (ROI), here is a BMR scenario:
If the national average for Windows server downtime is $15,000 an hour (and this is a fairly modest sum),
then this would mean that every minute of downtime equals $250. If it then takes a standard bare metal
disaster recovery solution approximately 20 minutes, as opposed to 40 minutes using file-by-file backup and
restore, the 20 minute savings using the BMR solution equates to a $5,000 dollar savings in downtime cost
with its first use.
Expanding on this, if the price of a premium BMR solution is $1,000 per server, an organization could
subtract the price of the BMR software from the money they saved on restore times. Bottom line, the company
would still be left with a $4,000 cost savings. Not many products offer a ROI like this, particularly after
just a first time use. In a real production environment, the time savings is more like a 6-to-1 ratio,
leading to even greater savings as opposed to the 2-to-1 ratio used in this example.
THE BMR STEPS
To give organizations a better understanding of how the two backup methods differ, we have provided a
procedure comparison between using file-based backups and restores versus image-based backups and restores.
File-by-file restore example:
- Install EISA Partition (53 minutes)
- Install Windows OS (45 minutes)
- Install Backup Software (5 minutes)
- Create Data Partitions (10 minutes)
- Restore System 4GB drive (35 minutes)
- Restore System State/Registry (1 hour)
- Reboot Server (2 minutes)
Total Restore Steps = 7
Restore Time = 3 ½ hours
Bare Metal Recovery example using UltraBac Software's UBDR Gold:
- Boot server using UBDR Gold Restore Media (5 min)
- Connect to a UNC path and initiate a 10GB OS partition restore with a conservative 2GB/minute transfer
rate (8 minutes)
- Reboot Server (2 min)
Total Restore Steps = 3
Restore Time = 15 minutes
As the example demonstrates, a BMR solution can easily restore a failed machine's 10GB OS partition in
15 minutes using a conservative 2GB/minute restore speed on a Gigabit network connection. Fast systems can
experience over 5GB/minute restore speed. Organizations using the BMR process now "complain" that the
machine boot time takes longer than the physical restore. When comparing file-by-file methods with BMR,
there simply is no comparison.
SUMMARY
Buying and implementing a BMR solution has become a priority for many organizations – and it should be.
BMR is a key part of any formal disaster recovery plan. It not only offers a fast means of restoring a
failed server, but also offers extraordinary benefits to expedite recovering from a catastrophic event. With
the ability to recover to dissimilar hardware and/or virtual environments, organizations can provide a clear
path to recovering lost servers by taking off-site backups to any number of service companies who can
provide temporary equipment. Rather than attempt to locate exact hardware matches or conduct laborious file
restores to new equipment, users can restore an image of a Dell server to an HP or IBM server. Using the
right BMR solution, companies also have the ability to restore multiple physical servers to a VMware ESX
host machine, and be up and running in literally minutes.
With the technology available today, it is no longer acceptable to have a file-by-file backup solution
as the only means of protecting data. Whether an organization has a single server, or over a thousand, a
bare metal recovery solution is a necessary preventative measure against expensive and unnecessary downtime.
BMR should be an integral part of every disaster recovery plan.
© Copyright 2007 UltraBac Software. All rights reserved. UltraBac Software, UltraBac, UBDR Pro, UBDR Gold, UltraBac Software logo, and Backup and Disaster Recovery for Business are trademarks of UltraBac Software. Other product names mentioned herein may be trademarked and are property of their respective companies.
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