LTO5 tapes have wrong capacity (35,4GB) instead of 1,5TB

[alberts]

Hi,

Case ID: 03837892

We are testing Veeam Backup & Replication CE. We have IBM TS3100 Tape Library with LTO5 Drive, both with IBM newest drivers 6.2.6.8.
LTO5 tapes are visible with 35,4GB capacity, instead of 1.5TB. Has anyone encountered same problem?

Tested on Windows Server 2012R2 and Windows Server 2019 [Tape proxy mode]

[Egor Yakovlev]

Hi Albert.

Looks strange. I would start by checking with official IBM Tape Diagnostic Tool to see what IBM sees as capacity for those tapes.

Thanks!

[JPMS]

We had this problem. Capacity kept decreasing each time we used a tape.

In our case the tape drive was faulty and had to be replaced. I would follow Egor's advice but would run a full tape test to see if you are getting errors. Don't forget to stop Veeam tape services before you run the diagnostic tool.

[Dima P.]

The capacity issue maybe caused by tape media degradation, especially when you use a specific tape cartage to read/write data continuously. When tape drive cannot write a portion of data to the specific tape area, it will mark it a corrupted and retry to write the data to the next area (when multiple areas are skipped - you get a noticeable decrease in capacity). Cheers!

[Stefano_Fiori]

Hi folks, I had the same issues trying to use a previously allocated set of tapes.
Those tapes were used in a backup routines using LTFS filesystem.
When I tried to inventroy on VEEAM even if I erased (always with VEEAM) the tapes, i got only 34,2 Gb Free.
The problem is the LTFS filesystem on the tape.
As suggested by Egor you have to use IBM Tape Diagnostic Tool , go on the tapeutils, Tape, use the command "open", then use the command "remove partition", then the command "close" (so you have not your device in use by ITDT anymore), close the application.
It will completly erase the partition Table, then you can inventory your tape using VEEAM.

Greetings

Stefano Fiori

[Dima P.]

Hello Stefano,

Indeed if the tape media was allocated by any other file system (for instance LTFS) full erase is required to get allocated space back to the LTO capacity. Thank you for sharing!

[aminbaik]

Hello,
I have hp lto7 tap driver,
when I access it using hp ltfs its show me that is 5tb but when I enable it on Veeam it's give me that the tape is 99gb ,,,, I am use version 9.5 update 4
so where is the problem ?
thanks.

[Egor Yakovlev]

Hi Amin,
I have moved your post to the respectful forum thread.
Please note that LTFS partition on said cartridge must be deleted(via full tape erase) in order for Veeam to see it's full capacity.
Thanks!

[northcide]

Hello,
I have hp lto7 tap driver,
when I access it using hp ltfs its show me that is 5tb but when I enable it on Veeam it's give me that the tape is 99gb ,,,, I am use version 9.5 update 4
so where is the problem ?
thanks.

Were you able to resolve this? I seem to have 1 tape doing this out of the 8 in the library.

Thanks

[RobTurk]

LTFS divides the tape in two partitions. Partition zero is one stripe (or wrap) long, and depending on the LTO version between 30 and 50GB in size. It is used to store LTFS index and metadata information.
Partition one is the remainder of the tape and contains the actual data blocks of your files.

Problem is that tape drives by default load partition zero, which means you only get the capacity of a single wrap.

If you still have the LTFS software installed on your system, you can remove the partition by running 'mkltfs --wipe'. This restores the tape to a single large partition. Note: Make sure LTFS and Veeam are not both active at the same time to avoid conflicts.
If you do not have access to LTFS then a vendor tool such as IBM ITDT or HP LT&T can remove the partitions from tape.

Note that there is another possibility for LTO tapes to show reduced capacity, even with a single partition. Diagnostics tools such as ITDT can programmatically reduce the capacity of a tape to allow quicker 'full tape' testing. Once set, you also need to use diagnostics tools to revert to the full capacity, using a Set Capacity command.