[Martin Greenwood]

The H680 card is fine, just put it an enclosure like this

https://www.sonnettech.com/product/echo-express-sel-tb3/overview.html

Then you will have a Thunderbolt 3 (or 2 with adaptor) unit with same performance and size as the SH3128 for about $220 !
You can then connect both your old and new LTO drives to any Thunderbolt Mac.

As Jerzy says it could be worth waiting for LTO-9. However because there was a delay with LTO-8 media so I suspect it will be late next year for LTO-9, but there is no definite date.

Best,

Martin

CTO

YoYotta.com

[Martin Greenwood]

You need to divide the price by the capacity, rather than the other way around, also the usable space is a bit less, so…

LTO-6 is $23/2.35TB = $9.78 per TB
LTO-8 is $160/11.7TB = $13.67 per TB

LTO-8 media will probably drop in price over the next few months, but at the moment it’s more expensive.
You can also look at using LTO-7 media as this is currently cheaper than LTO-8 per TB and is the same faster speed.

What LTO drive make and type do you have currently ? If it has a thunderbolt interface then it probably has a SAS daisy chain output. Assuming it’s the correct SAS controller inside then you can buy an external SAS LTO-8 drive. This will be about half the cost and will connect to your LTO-6 drive using a SAS cable.

Best,

Martin

CTO

YoYotta.com

[Martin Greenwood]

LTO-7 drives will attempt to speed match to the incoming data rate, however they need at least 100MB/s to write continuously. Below this speed they will have to stop, rewind and start again, you will hear this “shoe shining” behaviour if you listen to the drive. When this happens your average speed will drop drastically.

A 1Gb network will provide ~ 90MB/s assuming a fast enough source, reasonably sized files and no contention with other storage users. This will not be enough to keep the tape moving.
A figure of 125Mb/s is a theoretical 1Gb network speed using test data and jumbo packets.

If testing with an internal drive ensure it is an SSD rather than an HDD.
The fact that your verification is running normally suggests that there are no other issues.

Best,

Martin

YoYotta.com

[Martin Greenwood]

To write at full speed to an LTO-7 tape your source will need to supply at least 300MB/s. So your limitation will be the 1Gb network speed.

As a test try archiving a few hundred GB of files from a local SSD or direct attached RAID to tape and see what speed you get.
Can you get a 10Gb link to your shared storage?

Best,

Martin Greenwood

CTO

YoYotta.com

[Martin Greenwood]

None available in Europe, however I heard a good rumour that supply will resume over the next few months.

As Jerzy said you can use Type M tapes, however I would suggest buying ordinary LTO-7 rather than pre-initialised ones. Then use an app like YoYotta LTFS to init as Type-M as required. The reason is once initialised as Type-M they cannot be used as regular tapes in a LTO-7 drive.

Best,

Martin Greenwood

CTO

YoYotta.com

[Martin Greenwood]

It is possible that the previous LTFS install is the issue.

Quit YoYotta and then in the Finder select and delete the ICU, OSXFUSE and LTFS frameworks.
Their location is shown in the attached screenshot.

Then run YoYotta again and click the LTFS button to automatically install.

If still an issue please contact support@yoyotta.com and we can help further.

Martin Greenwood

CTO
YoYotta

[Martin Greenwood]

You can use either the ATTO H680 or H1280 inside the Sonnet chassis, both work well with LTO and LTFS.

More details here on our website.

https://yoyotta.com/help/installATTO.html

Martin Greenwood

CTO

YoYotta

[Martin Greenwood]

This thread started in Dec 2017 and now in Sep 2018 LTO-8 tapes whilst available, are still expensive.

So my recommendation is still the same. If you have existing LTO-5 and LTO-6 tapes then the LTO-7 drive is ideal.
You can create new LTO-7 archives at high speed, whilst still being able to read+write LTO-6 and read LTO-5.

If you don’t have older tapes or you will be keeping your LTO-6 drive, then an LTO-8 drive would make sense.
The drive does not cost much more and for now you can create LTO-7 archives. Then use LTO-8 tapes when they reduce in price.
But remember the LTO-8 drive doesn’t read LTO-6 tapes.

I don’t think LTO-9 drives will be available until at least 2020 and they will read+write LTO-9 + LTO-8 and should read LTO-7. This means LTO-7 tapes will be easily readable for many years.

But what about Type M tape formatting (a tape with an M8 barcode), which stores 50% more data on LTO-7 tapes using an LTO-8 drive ?
So it’s an LTO-7 tape with a special format that you can’t access using an LTO-7 or LTO-9 drive.
For long term archive, which is what the film + television industry needs, this is not good and we don’t recommend it.
For other industries that create short term recycling tape backups then Type M may make sense.

Best,

Martin

CTO

YoYotta.com

[Martin Greenwood]

The index size probably isn’t relevant. I would guess this is just a difference in the earlier LTFS format.

Was the first tape you tried write-protected from the start?
I would suggest trying another tape and ensuring it’s write protected before loading.

Then see if your files are visible after mounting.
If not then at least you can perform the roll back mount command to access files on the tapes.

Best,

Martin

YoYotta.com

[Martin Greenwood]

After rolling back what is the output from the mount command? Keen to see if the Index is showing some space used now.

I agree that it’s odd if all tapes are like this. Only thing I can say is in past we have done a lot of forward and backwards version mounting of LTFS tapes without seeing any data disappear.

Also what was the initial output of the ltfsck -l 0 command ?
When was the last generation written ? This timestamp is the update to the tape that wiped the data so the date might give you a clue as to what has happened…

Martin

YoYotta.com