Nicely done, Mark!

The cost of maintenance is difficult to summarize briefly, but over 30 
years with both spinning disks and LTO, regeneration will need to be 
done. LTO is a write one back, read two back, so when you install LTO9 
drives, you'll then need to migrate all the LTO7 tapes to LTO9.

Server frames and possibly HDDs need refreshing every 7 years or so if 
they are to be reliable. I've seen more failures after 7 years.

Access, of course, needs to play a role in this. For example, I 
regularly access some small subsection of my images (approaching 3 TB) 
and the audio that I've retained gets accessed. It looks as if you're 
archiving a large percentage of the work you have done. It's a good 
idea, but it depends on the client and the future potential. It's a 
business decision.

It gets very complicated. Quickly.



On 1/28/2016 12:50 PM, Mark Donahue wrote:
> Richard,
> I did a quick calculation based on what I have in the vault today and came
> up with some interesting numbers about the direction of data storage rates.
> Umatic 500 * 2 * 0.35GB=350GB (1981-1996)
> DAT 600 * 2 * 0.65GB=780GB (1988-2000)
> CD-R 900 * 0.75GB=675GB (1992-2010)
> 3324 200 * 12 * 0.75GB=1800GB (1988-2000)
> DTRS 800 * 8 * 1GB=6400GB (1997-2006)
> Hard Drives 600 * 1500=900000GB (0.9PB) (2001-Present) (This is a
> guesstimate. In the beginning there are some 100 and 500GB drives, but we
> have been burning though about 100 3tb drives a year for the last 3 years
> and it is only getting larger)
> At LTO7 prices of $48/TB for redundant copies plus $6000 for a pair of LTO7
> drives, is virtually identical to a pair of 12 drive storage servers with
> spinning discs at $52/TB 10 drive RAID6 with 2 hot spares.
> The bigger difference here is the cost of electricity. A pair of servers
> running 24/7/365 is about $900/year. (3741kWH * $0.12=$445/yr each)
> So by my calculation, up to around 50 TB it makes sense to have online
> spinning storage, beyond that offline tape makes more sense.
> All the best,
> -mark
> On Thu, Jan 28, 2016 at 10:54 AM, Richard L. Hess <[log in to unmask]>
> wrote:
>> 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 of times.
>> 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 was
>> an easy warranty replacement.
>> My main server states.
>> Used: 8.45 TB
>> Available: 7.41 TB
>> Cheers,
>> Richard
>> 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.
>>> Cheers!
>>> Corey
>>> Corey Bailey Audio Engineering
>>> On 1/27/2016 4:36 PM, Tom Fine wrote:
>>>> <SNIP>
>>>> 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
>>>> topics.
>>>> 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?
>>>> Thanks,
>>>> Mark
>>>> 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
>>>>> PC.
>>>>> 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
>>>>> them.
>>>>> Cheers,
>>>>> Richard
>>>>> --
>>>>> 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.
Richard L. Hess                   email: [log in to unmask]
Aurora, Ontario, Canada                             647 479 2800
Quality tape transfers -- even from hard-to-play tapes.