I am not familiar with your tape units but when I started using Exabyte
Mammoth2 scsi drives and tapes, 60gb native, 150gb compressed I saw
exactly the same thing. Then the hammer dropped! I started getting some
fsr (forward search record) errors. In compressed mode the tapes were
able to hold more blocks of data than the the scsi command set could
count in it's 3 byte counter. My data was being lost along the way. The
problem is now documented and will be fixed in a future release. The
only work around was to use non-compressed format. In my case, format is
M2 instead of M2C.
If this is also your problem you need to correct it pronto because your
tpe storage pool is losing client data!
Jim Taylor wrote:
>
> How much can these 100GB native tapes hold?
>
> Can I really be getting this kind of compression?
>
> Half a TB on one tape? Anyone else seeing this?
>
> My real issue is with the Status. It says that the tape is still filling,
> yet its Pct Util is only at 95%.
>
> I don't get this. I thought that a tape get to 100% full and the Est Cap
> keeps increasing until EOT is met. At which time the Status changes to Full
> and the Pct Util can then drop from 100% as the data on the tape expires.
>
> Have I been wrong???
>
> tsm: TSM-D2>q vol
>
> Volume Name Storage Device Estimated Pct Volume
> Pool Name Class Name Capacity Util Status
> (MB)
> ------------------------ ----------- ---------- --------- -----
> --------
> /tsm/tsmstg/disk-vol01 DISKPOOL DISK 5,000.0 30.5 On-Line
> A00000 TAPEPOOL LTOTAPE 100,000.0 7.2 Filling
> A00007 TAPEPOOL LTOTAPE 204,800.0 2.6 Filling
> A00023 TAPEPOOL LTOTAPE 384,482.9 65.0 Full
> A00031 TAPEPOOL LTOTAPE 398,471.2 64.4 Full
> A00035 TAPEPOOL LTOTAPE 537,664.2 85.3 Filling
>
> tsm: TSM-D2>
>
> > Jim Taylor
> > Senior Associate, Technical Services
> > Enlogix
> > * E-mail: jtaylor AT enlogix DOT com
> > * Office: (416) 496-5264 ext. 286
> > * Cell: (416)458-6802
> > * Fax: (416) 496-5245
> >
> >
--
Steve Bennett, (907) 465-5783
Steve Bennett, (907) 465-5783
State of Alaska, Information Technology Group, Technical Services
Section
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