HPE LTO-7 Ultrium on Veeam shows only 5Tb instead of 15 Case #05095184

[riad13]

Case #05095184
HELLO, I HAVE A LITTLE PROBLEM LATELY I PUT A HPE LTO-7 ULTRIUM OF 15 TB BUT WHEN I CHECK IT ON VEEAM IT SHOWS ONLY 5 TB ?.

[Andreas Neufert]

LTO7 has a raw capacity of 6TB which are a bit more than 5TiB which we show in our UI.
Veeam usually do not use the tape compression as our backups are stored usually compressed already.

[riad13]

Sorry I didn't get it ! Please explain to me more
I've put 3 data cartridge of 15 TB but when I look at media pool 1 , 2 and 3 I see only 5 TB as storage capacity in each one

[Andreas Neufert]

15TB is the maximum capacity that you can get out of LTO tapes under ideal LTO Tape drive internal compression.
For whatever reason the tape media and drives are advertised with the capacity before compression.

The native capacity of a LTO tape is 6TB. Which is a bit more than 5TiB. Check the internet for the conversation ratio between those and what this is. Basically disk vendors show capacity differently calculated then operating systems (and so Veeam) would do.

In case of compression and example.
You want to backup a 10TB VM directly to tape with tape compression enabled. Then 10TB of data is transported to the tape drive and the tape drive internal compression compress it to ~5TB (or less) data.

With Veeam you read the 10TB of data and write it compressed (software) to a disk => ~5TB (or less) data. Then copy those 5TB backup to tape (with disabled tape compression). Result is the same on tape (roughly). But with Veeam approach it can be up to 2x faster tape processing as you have to send only half of the data to the tape drive.

[soncscy]

I love your answer Andreas, but I think it can be simplified

Tape marketing is garbage and they advertise the capacity as "max capacity of compressed data"; this isn't want you want to focus on.

Focus instead on the __RAW__ capacity. (Sometimes called "uncompressed"): https://www.amazon.com/HP-Ultrium-Tape- ... S5G7&psc=1

Look here and notice the huge asterisk next to the capacity and how the description says 6/15? 6 TiB is the raw (uncompressed) capacity. If you use any space savings on your disk backups (compression or deduplication), 6 is the max capacity you'll get.

This is a dirty marketing trick by tape manufacturers and I'm perennially annoyed that they are allowed to continue doing it. But the smaller of the numbers you'll see on tape boxes is __always__ the "real" capacity.

[Andreas Neufert]

Here is a good overview... as well list TB and TiB. TiB is what the OS is using and you can find it in our UI. Rounded to 5TiB.
https://www.ibm.com/docs/en/ts4500-tape ... d-lto-tape

[tgx]

Dragging this thread up from the dead.
I have a Quantum Ultrium 7 HH7 attached to Veeam 11a server.
The advertised tape storage capacity is 6/15. Veeam 11a reports
the tape capacity as 1.5 under Windows Server 2016 Std.

[tgx]

Nevermind. I found out the tape was formatted at a lower capacity.