AMTAPETYPE(8)

📦
version 3.5.4 · 8 versions
, in ubuntu stonking

💖 AMTAPETYPE 💖

okay bestie, sit down, hydrate, and let me tell you about amtapetype — it's an 8th-section system administration command and it's lowkey one of the most useful little gremlins in the Amanda family. 💅

✨ NAME ✨

amtapetype — generate a tapetype definition by testing the device directly

🌸 SYNOPSIS 🌸

amtapetype [-h] [-c] [-f] [-p] [-b blocksize] [-t typename] [-l label]
           [-o configoption...] [config] [device]

🦋 DESCRIPTION 🦋

so amtapetype literally generates a tapetype entry for Amanda, and the way it does that is by testing the device directly. no middleman. no vibes-based guessing. it just goes and pokes the actual hardware. iconic behavior tbh 🫶

🎀 OPTIONS 🎀

⚠️ heads up queen — the options for amtapetype changed in version 2.6.1. if you're reading an ancient tutorial, that's why nothing matches. 💀
  • -h — display the help message. simple. polite. slay.
  • -c — run only the hardware compression detection heuristic test, then stop. this one only takes a few minutes, so it's the lil snack-sized run. 🍓
  • -f — run amtapetype even if the loaded volume is already labeled. for the bold ones.
  • -p — run only the device property discovery. that's it, that's the whole job.
  • -b blocksize — the block size to use with the device. default: 32k.
  • -t typename — the name to give to the new tapetype definition. name your baby. 👑
  • -l label — the label to write on the tape. default is randomly generated, so if you don't care, the universe picks for you. 🌈
  • -o configoption — see the "CONFIGURATION OVERRIDE" section in amanda(8).

if a configuration is specified, it gets loaded and used to configure the device. but listen, and listen closely bestie: global configuration parameters are not applied to the device. so if you need properties applied to a device in order to run amtapetype, you gotta supply those properties in a named device section. no cap. 🙈

💜 EXAMPLE 💜

generate a tapetype definition for your tape device:

% amtapetype -f /dev/nst0

look at you go. main character energy. ✨

🔥 NOTES 🔥

if the device can't reliably report its compression status — and as of this writing, no devices can do so 😭 — then hardware compression is detected by measuring the writing speed difference of the tape drive when writing an amount of compressible and incompressible data. so if your tape drive has very large buffers, or is just extremely fast, the program could fail to detect hardware compression status reliably. it's doing its best.

volume capacity is determined by writing one large file until an error — interpreted as end-of-tape — is encountered. then, in the next phase, about 100 files are written to fill the tape. that second phase will write less data, because each filemark consumes some tape. with a little arithmetic, amtapetype calculates the size of these filemarks. math girlie behavior. 🧮

now here's the messy part: all sorts of things might cause the amount of data written to vary enough to generate a strange filemark size guess. a little more "shoe shining" because of the additional file marks (and flushes), dirt left on the heads from the first pass of a brand new tape, the temperature/humidity changing during the multi-hour run, a different amount of data being written after the last file mark before EOT was reported, etc. it's giving chaos. it's giving entropy. 🌀

and note that the file mark size might really be zero for whatever device this is — and it was just the measured capacity variation that made amtapetype think those extra file marks in pass 2 actually took up space. so like… don't @ it. 🙈

💖 SEE ALSO 💖

the Amanda Wiki: : http://wiki.zmanda.com/

👑 AUTHORS 👑

and that's the whole page, bestie!! this little gem ships with Amanda 3.5.4, dated 08/26/2026 — go forth, label your tapes, and absolutely slay your backups. periodt. 💅✨🎀🦋

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