I concur with Corey here--I responded to Tom's new thread at greater
length, but tape was much more economical than spinning disks a decade
ago, and both have scaled upwards, moving the crossover point.
I'm now at the 10 TB level for dual RAID-6 local storage with an
additional 5 TB of single RAID-6 local storage.
A funny story about Sony marketing. In the late 1990s they showed a
robot that could hold 1000 TB of data on tape. They called it the
Peta-File. The next year, it was changed to Peta-Site. That was a decade
and a half ago.
My contention is that tape does not make sense for data storage until
you have a complete robotic system which includes tape cassette usage
history and automatic regeneration of tapes that have been used a number
While the number of "full file passes" on LTO tape has increased, it is
still relatively low and it's not useful for storage with many retrievals.
Anything that requires manual storage module shuffling is doomed to not
be used as regularly as necessary--personal experience with my off-site
backup confirms this.
Here is an example of where I think LTO tape (and I think LTO is now the
only viable data tape format) becomes useful:
This is a continuation of what I knew as ADIC storage, they were bought
out by Quantum in 2006.
It is now a no brainer (in my opinion) to provide 10-20 TB in a single
RAID-6 enclosure. Eight 3 TB drives in a RAID-6 configuration provides
for about 15.8 TB of usable storage. Going to 4 TB drives would increase
that to about 21 TB. (Rememeber, drives are measured using 1000X
multipliers while files are measured using 1024X mulipliers. Linux
properly calls those numbers TiB and GiB (for binary).)
6 TB drives are commonly available now in RAID-tuned HDDs and for backup
use (not server use) the WD Red drives seem to be good. I am using this
line in 2, 3, and 4 TB (8, 8, 5 of each, respectively). So far, I had to
replace one 3 TB (which were new at the time) about 8,000 hours in...it
was an easy warranty replacement.
My main server states.
Used: 8.45 TB
Available: 7.41 TB
On 1/27/2016 8:57 PM, Corey Bailey wrote:
> Hi Tom,
> The answer is relatively simple: Money
> You and I think about storage in terms of a Terabyte or two. General
> Motors and corporations of that size have to think in terms of multiple
> Peta-bytes. LTO becomes the least expensive method. After the data is on
> the tape, verification and migration is done robotically.
> Those that are considering LTO need to know that the format (drives,
> etc.) is only backward compatible for two generations and LTO-7 is on
> the horizon.
> Corey Bailey Audio Engineering
> On 1/27/2016 4:36 PM, Tom Fine wrote:
>> Could someone explain why a somewhat antiquated magnetic tape-based
>> storage system is preferable to several copies across several hard
>> drives? I just can't see any sense in using tape systems anymore for
>> data security, but I'm not a computer-storage expert, just a guy who
>> stores a lot of data.
>> -- Tom Fine
>> ----- Original Message ----- From: "Hood, Mark" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Wednesday, January 27, 2016 6:41 PM
>> Subject: Re: [ARSCLIST] LTO vs HDD
>> Hi Richard,
>> Thanks as always for sharing your experience and insights on all of these
>> Would you be comfortable sharing the make and model of the RAID-6 NAS
>> units you are using, and any comments about how well they have performed
>> to your expectations?
>> Mark Hood
>> Associate Professor of Music
>> Department of Recording Arts
>> IU Jacobs School of Music
>> On 1/27/16, 3:36 PM, "Association for Recorded Sound Discussion List on
>> behalf of Richard L. Hess" <[log in to unmask] on behalf of
>> [log in to unmask]> wrote:
>>> Hi, All,
>>> I saw this thread and was going to ignore it, but decided not to once I
>>> found out that RDX was HDD-in-an-otterbox merci, Henri, and thanks for
>>> the image, Lou. Otters are wonderful--see "Ring of Bright Water" (The
>>> book) and Point Lobos State Park.
>>> LTO was around while I was still doing broadcast consulting and, at the
>>> time (late 1990s, early 2000s).
>>> I struggled long and hard about how to store things and realized if I
>>> were going to become involved with LTO, I would need two drives (how
>>> else can you be even remotely certain that your tapes are readable once
>>> your single drive dies--I certainly saw that in the early days of PC
>>> tape backup. At that point, the cost becomes excessive.
>>> My philosophy now is: Any data I want to keep does not live solely on a
>>> I have two in-house RAID-6 NAS units, one backing up the other; an ammo
>>> case of 2.5-inch HDDs off-site (2 TB 2.5-inch USB 3.0 drives are pretty
>>> economical these days and are USB-powered).
>>> One son has been migrated to the cloud where Dropbox backs up and
>>> mirrors his two on-site laptops. Here, I harvest all new files (but not
>>> updates to prevent pollution of existing files) and store them on my
>>> RAID-6 NAS units to protect against a Dropbox failure or hacking. The
>>> other son will do it soon, but the first one is potentially going far
>>> away to school next fall for his Masters (Wichita and Edmonton are on
>>> the list) so I wanted to get some closer-in history with the system.
>>> RAID-6 allows the failure of any two disks without losing data and the
>>> data does not have to be chopped up into 1 or 2 TB chunks as it does
>>> with HDDs.
>>> I do not keep CF/SD cards, I copy and verify the copy and then recycle
>>> Richard L. Hess email: [log in to unmask]
>>> Aurora, Ontario, Canada 647 479 2800
>>> Quality tape transfers -- even from hard-to-play tapes.
Richard L. Hess email: [log in to unmask]
Aurora, Ontario, Canada 647 479 2800
Quality tape transfers -- even from hard-to-play tapes.