[Tim Jones]

The main thing that makes these “Archive” drives is that they’ve reduced the rotational speed (and a few other less pronounced diffs), sacrificing performance for higher levels of reliability. It is interesting that they don’t specify the RPM ratings in the specs any longer, but that was discussed when these drives were first introduced.

The result is an 800Khr MTBF rating with vary low vibration and and very low (relatively) power consumption.

However, the tech is too new to provide an unpowered shelf life expectancy, and THAT is one very important thing to keep in mind for long term archival strategies.

I’f you;re building a huge storage environment and power needs are built into the budget modeling, then these drive could provide a very good mid-range solution. However, unless you’re a large scale operation, keeping large numbers of disks powered for indefinite periods may not be fiscally possible.

LTO will always be the most cost-effective solution for long term archival with no power requirements and ease of storage (~1.8¢ / GB for LTO-6) with Sony’s ODA or other optical media (Blu ray, etc) being better alternatives than disk.

HTH,

Tim
—
Tim Jones
CTO – TOLIS Group, Inc.
https://www.tolisgroup.com
BRU … because it’s the RESTORE that matters!

[Tim Jones]

Sorry – I totally missed that you were using ShotPut PRO for the offloading and copies (I’m still trying to get used to the new Cow forum look and workflow 🙂 ).

The difference is that rsync/rsyncX do the checksumming transparently and any errors are recognized at the point of copy rather than after the fact and with a separate sidecar checksum database/file.

Tim
—
Tim Jones
CTO – TOLIS Group, Inc.
https://www.tolisgroup.com
BRU … because it’s the RESTORE that matters!

[Tim Jones]

In that case, I would recommend using something like rsync or rsyncX (rsync with a GUI) since they perform checksumming at the time of the file copy to the destination automatically. It would be the same as performing an MD5 on the source end, copying the files to the destination end and then re-running the MD5 on the destination copy, and then comparing the MD5 results.

Any other mechanism would involve manual processes to generate the checksums and that can lead to the loss of the sidecar MD5 values leaving you with no option to verify the copied files.

As an aside, you could buy an LTO Thunderbolt solution and use it to provide the LTO side of the equation as a service for the users regardless of their size. LTO-6 tapes are only around $30 each, so there’s a potential for a new service offering for your customers.

Tim
—
Tim Jones
CTO – TOLIS Group, Inc.
https://www.tolisgroup.com
BRU … because it’s the RESTORE that matters!

[Tim Jones]

Hi Paul,

Are you strictly working with disk or is LTO coming into this process?

Tim
—
Tim Jones
CTO – TOLIS Group, Inc.
https://www.tolisgroup.com
BRU … because it’s the RESTORE that matters!

[Tim Jones]

I just realized that you’re still using 3.1.5. A good start would be to update that to the 3.1.19 that will be release later this morning.

You can download it now from:
https://www.tolisgroup.com/downloads/brupe/BRU_PE_Rel_3.1.19.dmg

The announcements and changes will be going out to the announcement list after lunch.

Tim
—
Tim Jones
CTO – TOLIS Group, Inc.
https://www.tolisgroup.com
BRU … because it’s the RESTORE that matters!

[Tim Jones]

Hi Pedro,

Frist, the RR 2711 is not truly tape aware, so it could be that you were just lucky before your change of OS versions.

However, having said that, did you update the firmware on the card and then update the drivers to the latest from the HPT website?

Only the 2722, 4522, and 6328 are updated to properly support tape.

Tim
—
Tim Jones
CTO – TOLIS Group, Inc.
https://www.tolisgroup.com
BRU … because it’s the RESTORE that matters!

[Tim Jones]

That’s what the test will tell us. IngestPRO should have been able to suss out all of the sets on the tape. The layout results that you get from that test will tell us if you have a scenario that we’d not thought of.

Tim
—
Tim Jones
CTO – TOLIS Group, Inc.
https://www.tolisgroup.com
BRU … because it’s the RESTORE that matters!

[Tim Jones]

I believe that Kayleigh relayed that the tape layout for a Cache-A tape is not one single data set, but rather multiple data sets separated by filemarks. Also, the Cache-A process doesn’t guarantee that the files will be written onto the tape in any specific order, so to have files missing from one data segment would not be a surprise as they would be recovered in the process of extracting another segment.

Here’s a quick test that you can run in a Terminal (assuming BRU PE is installed) –

ERR=0
tapectl rewind
while [ $ERR -eq 0 ]
do
tapectl -v fsf
ERR=$?
tapectl tell
done

You should see multiple block addresses reported and finally a “blank check” error. How many segments are on one of those tapes?

Tim
—
Tim Jones
CTO – TOLIS Group, Inc.
https://www.tolisgroup.com
BRU … because it’s the RESTORE that matters!

[Tim Jones]

You could always just restore the Cache-A TAR tapes using the TOLIS Tape Tools that are included in the BRU PE package. While the default requires using the command line, we offer an add-on for BRU PE named ArGest IngestPRO that gives you a GUI front end if you’re either not command line savvy, or have more than a few tapes to deal with.

An example of restoring a Cache-A tape from the Terminal would be:

cd /Path/To/Restore/Location
taperead -f ntape0 -b 150K | tar -xvvf - -b 300


Tim
—
Tim Jones
CTO – TOLIS Group, Inc.
https://www.tolisgroup.com
BRU … because it’s the RESTORE that matters!

[Tim Jones]

The drive will prompt you (via the light on the drive) when it needs to be cleaned, but we do it a couple of times a year. The cleaning system is smart on the LTO drives and if it’s not needed, the process simply ejects the tape.

Tim
—
Tim Jones
CTO – TOLIS Group, Inc.
https://www.tolisgroup.com
BRU … because it’s the RESTORE that matters!