Data Backups Print E-mail

Does Your Data Even Exist?

Surprisingly, this is a very, very valid question. One of our favourite quotes is "Digital data doesn't exist until it can be found in two distinct locations at once", which is a quote from the late 1980s by a guy called Hilton Travis. Some of you may have heard of him. This is as true today as it was almost 20 years ago. If you have some data in only one location and don't have it archived anywhere, how can you prove it ever existed if it becomes accidentally deleted? And yes, three places is better than two.

The need for data backups will never be greater than when you realise that you didn't make any. Or you didn't check those that you made to ensure that you could reliably restore data from one recently. And this can be a trying time for your business. There's a strong possibility that your business will not survive a disaster where all of your data gets destroyed - who are your clients, your suppliers, and who still owes you money?



Disaster Recovery

We've probably all heard this term at least once. Its what happens when things go wrong, in place of the panic that starts to rise, and the result is (hopefully) that all your data is recovered. Disaster recovery can really only have a chance of being successful if there was a decent Disaster Recovery Plan in place before the disaster occurred. Disaster Recovery Planning (also known as Business Continuity Planning, for obvious reasons) is covered under an Australian Standard - HB 221:2004.



How Valuable Is Your Data?

In some businesses, almost the entire business value is in your data. In others, although there is a lot of value in stock and equipment, the data on your computer systems is still of an extremely high value - high enough that loss of this data could do serious damage to your business. Has your investment in a data backup solution taken this into consideration?  Do you perform regular restore tests on your backups to ensure they are valid?



Tape Drives

The most common form of data backup is still to a tape drive. There are a number of reliable tape formats of varying capacity available today, such as AIT, DAT, DLT, Super DLT and LTO 2. The amount of data you need to archive and the time you have available to archive this data will determine the type of tape drive that suits your needs.

If you have the need for more stroage than a single tape can hold, then you may need to look at tape autoloaders and tape libraries.  Although expensive, these can save a lot of time, frustration and effort when it comes to backing up large amounts of data.


Backup Methods
FormatCapacity (Uncompressed)Speed (GB/hour)
LTO 4 Tape Drive *Up to 800 GB per tape432.00 (estimated)
SDLT-S4 Tape DriveUp to 800 GB per tape216.00
SAIT-2 Tape DriveUp to 500 GB per tape158.00
SAIT-1 Tape DriveUp to 500 GB per tape108.00
LTO 3 Tape DriveUp to 400 GB per tape245.00
AIT-5 Tape DriveUp to 400 GB per tape  86.40
SDLT 600 Tape DriveUp to 300 GB per tape129.60
AIT-4 Tape DriveUp to 200 GB per tape  86.40
LTO 2 Tape DriveUp to 200 GB per tape  72.00
DLT VS320 Tape DriveUp to 200 GB per tape  57.60
SDLT 320 Tape DriveUp to 160 GB per tape  57.60
VXA-3 Tape DriveUp to 160 GB per tape  43.20
SDLT 220 Tape DriveUp to 110 GB per tape  39.60
AIT-3 Tape DriveUp to 100 GB per tape  43.20
LTO 1 Tape DriveUp to 100 GB per tape  57.60
AIT-2 Turbo Tape DriveUp to   80 GB per tape  43.20
DLT 8000 Tape DriveUp to   80 GB per tape  21.60
DLT VS160 Tape DriveUp to   80 GB per tape  28.80
VXA-2 Tape DriveUp to   80 GB per tape  21.60
DAT 160 Tape DriveUp to   80 GB per tape  24.84
SLR140 Tape DriveUp to   70 GB per tape  21.60
Mammoth-2 Tape DriveUp to   60 GB per tape  43.20
AIT-2 Tape DriveUp to   50 GB per tape  21.60
AIT-1 Turbo Tape DriveUp to   40 GB per tape  21.60
DLT 1 Tape DriveUp to   40 GB per tape  10.80
DLT VS80 Tape DriveUp to   40 GB per tape  10.80
DAT 72 Tape DriveUp to   36 GB per tape  12.60
AIT-1 Tape DriveUp to   35 GB per tape  14.40
DLT 7000 Tape DriveUp to   35 GB per tape  18.00
VXA-1 Tape DriveUp to   33 GB per tape  10.30
AIT-E Turbo Tape DriveUp to   20 GB per tape  21.60
DAT DDS-4 Tape DriveUp to   20 GB per tape  10.80
DLT 4000 Tape DriveUp to   20 GB per tape    5.40
Mammoth Tape DriveUp to   20 GB per tape  10.50
Travan TR-6 Tape DriveUp to   20 GB per tape    7.20
DLT 2000xt Tape DriveUp to   15 GB per tape    4.50
Mammoth-LT Tape DriveUp to   14 GB per tape    7.20
DAT DDS-3 Tape DriveUp to   12 GB per tape    4.32
Travan TR-5 Tape DriveUp to   10 GB per tape    3.60
DAT DDS-2 Tape DriveUp to     4 GB per tape    2.80
Travan TR-4 Tape DriveUp to     4 GB per tape    3.60
DAT DDS-1 Tape DriveUp to     2 GB per tape    1.98
Travan TR-3 Tape DriveUp to     1.6 GB per tape    0.45
Travan TR-2 Tape DriveUp to     0.8 GB per tape    0.23
Travan TR-1 Tape DriveUp to     0.4 GB per tape    0.23
Blu Ray DriveUp to   50 GB per disc  64.80 (4X Write)
Hard DriveUp to 750 GB per drive144.00 (P/SATA)
Hard DriveUp to 750 GB per drive144.00 (Firewire)
Hard DriveUp to 750 GB per drive126.00 (USB 2.0)
Iomega REV DriveUp to   35 GB per drive  91.44 (Outer tracks)
Iomega REV DriveUp to   35 GB per drive  45.72 (Inner tracks)
USB KeyUp to     8 GB per device  25.00 (average)
DVD-RAMUp to     4.7 GB per side  24.35 (5X)
CD DriveUp to     0.7 GB per disc  16.88 (32X)
Crossed FingersLet's hope we never have a failureNot enough
* These tape formats are not yet in the marketplace, but due out "real soon now"

Removable Hard Drives

An alternative method of backup where huge quantities of data are involved is a removable hard disk drive. The most common interfaces are USB 2 and Firewire, although Serial ATA (SATA) and hard drive caddies are also available. There is a temptation to use this drive as spare space for data storage which completely invalidates this drive as a "backup" drive in those cases. However, the most important thing that needs to be considered where removable hard drives are concerned is that hard drives are a very sensitive technology - a minor bump while operating can reduce the hard drive platter to a mess of screaming, grinding metal.

If you use external (or caddy based) hard drives as your backup method, please ensure that they are very, very carefully transported.  There are specially made external hard drives designed to provide the protection needed to keep your drive and its data safe - and there are a lot of unsuitable devices as well.



Recordable CD And DVD Drives and Media

If the amount of data you need to archive is less than 700 MB, then a recordable CD-ROM may well be suitable - it also allows your data to be recovered on almost any computer available today. If you have slightly more data - up to 4.7 GB - then a DVD-RAM drive is quite a valid solution. DVD-RAM drives are suitable for use in any Windows Vista, Windows XP and Windows Server 2003 computer and are recognized as a removable hard drive. That makes them rather easy to backup to. DVD-RAM drives are less common than DVD-ROM drives, but they are easy enough to locate when you need one - even new ones cost less than $150.

You can buy double-sided DVD-RAM discs that can store 9.4 GB of data, but you need to flip the disc over when you need to record on the second side, making an unattended backup impossible. They may allow you to put off buying a larger backup device quite so soon, but the time and effort involved in flipping the disc and slowing down the archiving of your data can be easily offset by purchasing an appropriate tape drive before your data grows beyond 4.7 GB.



Recordable Blu-ray Drives and Media

Blu-ray media comes in two main forms - BD-R which is a write once, read many (WORM) format - like a CD-R or DVD-R/DVD+R - and BD-RE which is an erasable format like CD-RW and DVD-RW/DVD+RW.  Please note that the BD-RE format is not similar to DVD-RAM, but DVD-RW/DVD+RW.  Currently, 25 GB and 50 GB BD-R (write once) media is available and 25 GB BD-RE (erasable) media is available.  Panasonic, Sony and TDK are almost ready to release BD-RE 50 GB media.

A 25 GB BD-R and BD-RE disc is a single layer disc that uses a blue laser to write and read the data, wherreas a 50 GB BD-R and BD-RE disc is dual-layered.  By utilizing a blue laser (wavelength = 405 nm) instead of a red laser (wavelength = 650 nm), more data can be stored on the same sized media (normal size is 12 cm, small discs are 8 cm).  TDK is proposing to extend the current Blu-ray specification to include their 200 GB BD-R prototype (this is a 6 layer disc).

At this point in time, not all backup software supports the use of Blu-ray drives and BD-R/BD-RE media, so you will need to confirm support for this before installing a Blue-ray drive only to find that you need to shell out another grand or so on backup software that will support it.


USB Keys

If your data backup needs are modest, then maybe a USB Key will suit. These come in sizes from 128 MB up to at least 1 GB and are compatible with any Windows XP and Windows Server 2003 machine, and most Windows 98 and Windows 2000 machines if you load the appropriate driver. They aren't as sensitive as hard drives, but a good drop to the floor may well destroy the data on a USB Key.

There is quite a performance difference between USB Key drives.  The Verbatim and Sandisk products offer quite decent performance for their price, and are both about double the performance of the PNY product that is rather common.



Backup Rotation

There are a number of different methods that you can use for rotating backup media, depending on the number of media devices you wish to purchase and the value that you place in your data.  The generally recommended methods are based on the Grandfather-Father-Son (or GFS) method of a monthly full backup held offsite, a weekly full backup held onsite and then rotated offsite, and daily incremental backups which are kept with the weekly backups.  Quark IT can design an appropriate Business Continuity Plan incorporating an appropriate Backup Rotation Plan for your business.



Offsite Storage

Whatever you do use for your data backup device, make sure that you have enough of your older archived data to recover anything you may need. Also, make sure you store at least one recent, valid backup offsite somewhere safe - maybe at home, maybe in another office, or maybe at a special offsite storage facility. We would also recommend storing an older know valid backup either with this current backup or in another safe place. Whatever you do, as this is your sensitive business data, you will need to make sure that this location is safe and secure - you don't really want your competitors going there to steal your data. That would defeat the purpose somewhat.



Business Continuity Planning

Quark IT can perform a Business Impact Analysis to identify crucial systems and the effect an outage would have, develop contingency plans to cover these issues, help in "live action" simulations of disasters (although, we don't control the rain just yet), maintenance and upgrading of your Business Continuity Plans and in the event of a disaster, we can help you execute these plans. Feel free to contact Quark IT to discuss backup and Business Continuity options to suit your needs.

 
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