LTO Tape - Facts & Figures

This article focuses on LTO technologyand provides you with a few pointers that should help you choose the most appropriate LTOgeneration for your backup needs. 

Very quickly LTO has become the leadingtape format for backup, accounting for the vast majority of tape sales. 

As you can see from the chart below thereare currently 3 shipping LTO versions.  Iexpect LTO-2 to be phased out soon, so unless you have a really tight budgetI'd go for LTO3 as a minimum.

Compressed datarates are commonly quoted at a 2:1 compression ratio.  To calculate the compressed data rate doublethe above quoted figures.

LTO tape capacity is typically quoted asNative/Compressed, e.g. LTO-2 wouldbe quoted as 200GB/400GB.  The firstfigure is the native capacity and the second figure the compressed capacity(2:1).  I would advise that if you arebacking up graphics data you base your figures on the native capacity.  Graphics files do not compress well.

As the chart suggests, if you are backingup a small amount of data a single tape may suffice.  For example if you need to backup 200GB, thenLTO-2 would seem the obvious choice. However take a look at the native transfer rate; 200GB can be restoredin approximately 2 hours.  Upgrade toLTO-3 and your data will be restored in well under an hour (...or, tell yourboss it will take two hours, deliver it in one, and when it comes to your nextcompany car upgrade feel free to suggest some extra options).

Larger amounts of data will requiremultiple tapes.  Simple maths will tellyou how many LTO tapes are required for your data.  Again it is important to look at the amountof time it will take to back-up/restore your data.  In certain circumstances additional drivesmay be required to provide the desired throughput. A twin LTO-4 driveautoloader will restore a whopping 864GB/hr but you could have 24 or moredrives in a tape array.

Finally, LTO is a robust tape with atypical day-to-day life of 5 to 15 years depending on the number of times youwrite to the tape.  If you are archivingto LTO you can expect a shelf life of between 15 and 30 years. 

For environments that require a permanentrecord of data, LTO 3 and 4 Write Once Read Many (WORM) offer a verycost-effective alternative to magneto optical archive media.

If you have any questions or feedback, drop us an email or call 0115 916 5519.

Andy Cain,

Server & Storage Consultant

**Price Drops - Call the sales line (0870730 6868) or visit www.jigsaw24.com for our latest pricing!**

Links & Resources

www.lto-technology.com

http://en.wikipedia.org/wiki/Linear_Tape-Open

Page created on 25 November 2008 by Alice Carr.

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