Transcript The new role of LTO

The new role of LTO-5:
LTFS vs. tar
HPA Tech Retreat
Palm Springs
February 17, 2011
©2011 Cache-A Corporation
The issues with using tape
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Data Portability
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Ease of Use
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Command-line vs. GUI
Self-Describing
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Standard for format on tape
Directory of a tape’s contents
Linear Nature
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Not random access
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Can’t freely delete content and recover space
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Data Portability
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The majority of tape-based solutions use
proprietary formats
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Only one open format has been available – tar
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LTFS now adds a second open format
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HP & IBM Interop proven in the demo room
©2011 Cache-A Corporation
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Ease of Use
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tar has been command-line driven and mostly
limited to tech-weenies
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LTFS offers accessibility from normal file tools
including:
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Windows Explorer
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Mac OSX Finder
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#4
Self-Describing Tape – a bit of history
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1987: SuperMac DataStream (Mac)
1992: QIC with QFA (DOS)
1996: DatMan (Windows)
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LTO (2000)
 2004-2007:
Quantum A-Series (networked)
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2008: Cache-A tar (networked)
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2010: LTFS (Linux, Mac, Windows)
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tar – a bit of history
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Originally in Unix in the late 1970’s
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tape archive
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Established POSIX.1-1988 standard in 1988
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POSIX.1-2001 revised extended tar a.k.a. “pax” format
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Unlimited pathname length
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Unlimited character set encoding
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Date/Time, Symlink, User/Group improvements
Mac, Windows, Unix and Linux versions available
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tar Format
tarball
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Cache-A tar Format
Cache-A Appliance
Disk
Catalog
Database
TOC
TOC
TOC
TOC
TOC
Additional
Metadata
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#8
LTFS Format
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LTFS Format
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Cache-A LTFS Format
Additional
Metadata
Cache-A Appliance
Disk
Catalog
TOC
TOC
TOC
TOC
TOC
TOC
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LTFS Issues
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Newly Minted, work to be done
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Not all file names supported
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Tape spanning not supported
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LTO-5 Only
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Long delays to update index upon eject
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Many ops cause tape thrashing
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LTFS does not work like a hard disk
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The Good News: LTFS Looks like Disk
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The Bad News: LTFS Looks like Disk
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If you treat it like Disk, you will have problems
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File fragmentation, performance issues
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i.e. Auto-Save
Multi-file operations
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i.e. Icon View
©2011 Cache-A Corporation
#13
Cache-A LTFS implementation
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Include Cache-A TOC on tape
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Include TOC in Catalog
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Include “URL encoding” to support
real-world file naming
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Handle linear transactions behind the scenes
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Plans for continued future enhancements
©2011 Cache-A Corporation
#14
Format Comparison
baseline
LTFS tar
Cachetar ALTFS
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Portable, Cross Platform
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Self-Describing
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Easy-to-Use
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©2011 Cache-A Corporation
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Format Comparison
baseline
LTFS tar
Cachetar ALTFS
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Single File Restore
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Multi-tape Volumes
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Library Option
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#16
Format Comparison
baseline
LTFS tar
Cachetar ALTFS
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Networked, Multi-user
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No Client-side Software
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Handles all file names
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©2011 Cache-A Corporation
#17
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Format Comparison
baseline
LTFS tar
Cachetar ALTFS
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Multi-tape Search
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Search Restore
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Technical Support
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©2011 Cache-A Corporation
#18
Summary
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LTFS is the only Self-Describing, Open Solution
Available
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tar is More Mature and More Ubiquitous but not
Self-Describing or Easy-to-use
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Appliance implementations like Cache-A’s can
improve both – neither is complete on their own
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#19
Thank You
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