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Tape storage

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I've never made a wiki page before. Please be patient with my autism.

What is it?

  • Tape storage is commonly used technology for creating backups in enterprise industry. However that didn't stop some autistic people to use it for home usage.
  • Magnetic tape is, along with optical and magnetic platters, one of common technologies to store data.
  • Tape is usually a long spooled magnetic tape wrapped up in a plastic case (like VHS, but not a floppy disk).
  • The size of tape is a result of tape length / width and density.
    • Density comes from from precision, i.e. how much physical area is needed to store a bit. Obviously the smaller then it's more dense.
    • There is often a term of raw storage and compressed storage (which is often estimated as 2x raw storage). Now be a smart anon and guess which size producers are printing out in labels?
    • Tapes are either regular R/W or WORM (write once, read many).
    • Tapes are subject of wearing out. Tapes often comes with counter of many times they were loaded.
    • Tape cleaner is another kind of tape used for maintenance. Often device will blink "clean" LED to indicate such action.
  • Streamer is a unit which:
    • loads up the tape. Either manually or with by some robot
    • performs R/W operations
    • on the other hand uses server-grade connection cable for communication (USB also happens to be used on small-scale solutions)
  • Tape library is a complex tool that:
    • can store more than one streamer
    • can store from hundreds up to thousands tapes
    • contains a "robot" which is able to pick those tapes and insert / eject those
    • tape cases are mostly labelled with barcode to help with robot navigating
    • And it is is fucking expensive. More than your whole NAS / backup investment is worth it already.
  • Tape solutions tend to have "generations", each aiming mostly for doubling it's size. But some features are being included as well.

Pros

  • Tape storage key advantage is cost effectiveness, as price per GB/TB is the best one compared to other types.
  • TBD: Better for long term storage than other solutions. Except for M-Discs
  • NOTE: Some better calculations needs to be done. Those on-sale shucked HDDs might beg to differ.

Cons

  • Huge entry investment.
  • Weak integration with OS in old solutions
    • As far I know may of the Windows 3rd party softwares are trial/paid versions.
    • I could not found FOSS software to handle tape backups.
    • The closes I could find is https://www.z-dbackup.com/datdump.html which handles a handful of tape formats. Sounds pretty neat, but free software is somewhat limited.
  • Slow R/W operations.
  • Also manually juggling the tapes is tiresome. Consider just how many tapes you need to make a full backup and how often would you need to do that?

Should I consider using it

Short answer: NO

Medium answer: Most likely not. The entry investment is pretty expensive.

Long answer: In general some calculations needs to be done to figure whether you should bother at all. Besides you don't want to manually handle dozens of tapes on regular basis.

If anything LTO-5 is absolute minimum you want to consider these days. LTO-4 and older doesn't have good capacity. Any other standards are not worth either. I mean go wild if you are retro freak or you HAPPENED to get streamer and HBA card for free. Tapes are pretty cheap and accessible.

Further analysis / strategies

First of all, there are TWO scenarios of I can think of:

  • archiving some stuff permament for long term storage
  • keeping regular backups on daily/weekly/monthly basis

Price analysis i.e. is it worth it?

So some anon kindly suggested to compare the price against shucked HDDs. To see if investment is worth at all.

Price analysis
Generation Streamer Price (ebay, usd) Single tape price Price to reach exactly 8TB
LTO-5 ~150USD? 20USD 106 USD
LTO-6 ~600USD? - -
LTO-7 2,249.00 - -
LTO-8 2,775.00 - -

How integration with OS looks like

Since LTO-5 and later LTFS had been introduced, which allows to treat loaded tape like a removable media on windows' explorer. Pretty great and works well with robocopy command.

Pre LTO-5 and and other tape solutions? Not such a thing. Either you need to use some 3rd party software (some windows versions had this "OS tape backup"??)

Dunno about linux, but in best case you can literally type commands to /dev/<tape> to rewind tapes and use dd command to make copies.

Parts

In order to work with that you will need the following:

  • For workstation a HBA card which will handle communication with unit.
    • Also consider that the panel size might be dedicated for server PC, not consumer PC.
  • Cable itself. Kid you not but it's expense by itself. Be wary as external and internal cables tend to differ.
  • Streamer unit. Which is the biggest cake and root of all problems.

Streamer has two categories.

First is:

Second is:

  • Internal - Most of those is 5,25" size so it should fit PC. Make sure your HBA has internal connectors.
  • External - Requires additional AC outlet. Make sure your HBA has external connectors. (is it just wrapped up internal inside some fancy case?)

HBA card

Host (bus) adapter in short just allows connect with devices via server-type cabling.

Common types

  • SCSI - old af. Don't bother with it. Unless you just like retro stuff.
  • SAS - SATA on steroids, still used
  • FC - optic stuff

Types of tape storage

  • LTO - the absolute leader in this industry. AFAIK, nearly every industry is using this.
  • DLT - Failed competitor to LTO
  • DDS - Latest gen was introduced in 2009 with raw 160GB
  • DAT - initially allowed cassette tapes to record music in digital format, later found uses for data storage