LTO3 A-Series vs. LTO4

[Jesse Korosi]

I have recently switched over from using an LTO 3 A Series deck creating Master Backups for clients and am now using an LTO4 deck, which I guess is not called an "A-Series".

Several people had directed me towards the regular LTO4 deck and BRU software as a better alternative then the A-Series LTO3. I guess my main question is, why is the LTO4 regular series the "Industry Standard" and what makes it better then the A-Series? From the few months I have been using the LTO4, it seems to have a lot of draw backs from the A-Series deck I was using before such as:

- Your tape could be opened simply through Safari, with the correct log in information assigned. Therefor you wouldn't need BRU or any other software to view or send something to the tape.

- Looking at what was on your tape was as simple as looking at what is on an external hard drive. (no archive or definition needed to be loaded)

- If an archive has been lost it is much more painful to find out what is on the tape. I have been shown the process through terminal, but comparing this to just popping the tape in is pretty painful.

- When I used to back up anything to my LTO3-A-Series, technically all I needed was the tape. Now I need paperwork to go along with it that states the Archive ID, Buffer Size etc.. and also a disc or usb key that will hold the actual Archive folder.

- And then once I deliver a tape with all of the paperwork and disc and or usb key I then have to (or at least should in my best interest) keep all of that on file in my office.... Versus just sending them the tape and if they ever came back all I would need is the tape.

- I guess there is something nice also about just being able to actually open up something to actually view what it within your tape. Not what an archived text file says is on your tape.

I am sure I am missing something or maybe it is as simple as the LTO4 is more stable? Either way any information would be greatly appreciated.

Thanks in advance,

 

[Jeff Kilgroe]

A Series is a problem because it is no longer developed or supported by Quantum. LTO-4 A-Series units are now being manufactured only by Cache-A and they are terribly overpriced. You are locked into using only their hardware as they have not opened up the tape format. Their tape format seems to not meet any of their claims about robustness, compatibility, etc.. In other words, it's nothing special.

BRU does need some extra documentation, but I guess that's why tapes come with labels, ya know... The archive folder is handy because it stores a copy of the tape directory so you can browse your tapes offline and then restore the specific file you need by just loading the tape you need. If you ever do lose your archive folder or forget to back it up, it can be rebuilt from the tape, it just takes time. You can always dump the entire contents of a tape to a drive volume without rebuilding the archive folder info too.

Many people have set up backup systems that do everything the A-Series does and more, using off the shelf solutions. The A-Series seems convenient at first, but there's really nothing special about it. There are tons of Java / web based front-ends out there that can be hosted on a backup server system and interfaced with your backup software, which will give you everything a Cache-A can do and more.

Unfortunately, there is no universally accepted tape format. Every tape format has its shortcomings or advantages. The advantage of A-Series is the surface-level convenience, but for most of us these days, the cost and single-vendor issues are too much compromise.

 

[Bruce Ingram]

As someone who has just recently been burned by issues with the LTO-3A I can only whole heartily agree with Jeff here.

 

[Tom Goldberg]

Cache-A here. I'd like to respond to a number of items in this thread...

A Series is a problem because it is no longer developed or supported by Quantum. LTO-4 A-Series units are now being manufactured only by Cache-A and they are terribly overpriced.

It is correct that Quantum has stopped their A-Series and Cache-A is offering a newer system with LTO-4 and LTO-5 tape drives. I take issue that they are terribly overpriced - at $7k for our Prime-Cache system, you don't save much by building your own solution with off-the-shelf software such as Bru or Retrospect if you include the cost of the host computer.

You are locked into using only their hardware as they have not opened up the tape format. Their tape format seems to not meet any of their claims about robustness, compatibility, etc.. In other words, it's nothing special.

This is completely untrue. Our format on tape is standard unix/linux tar and anyone can read tapes made in one of our systems with any tar capable system. We do indeed have customers successfully sharing Cache-A archived content with non-Cache-A recipients. A technical brief of how to read our tapes is posted on our support page. We make extensive use of tar's capabilities to assure robust and compatible archiving.

Some of what is special about our systems is explained below but readers may want to learn more about this in my white paper "Protecting Your Content: Archive vs. Backup" available on our website here.

- Your tape could be opened simply through Safari, with the correct log in information assigned. Therefor you wouldn't need BRU or any other software to view or send something to the tape.

Cache-A systems also provide a full web-based user interface allowing the ability to operate the system from a browser.

- Looking at what was on your tape was as simple as looking at what is on an external hard drive. (no archive or definition needed to be loaded)

Cache-A systems keep a full database catalog of every tape seen and allow you to view tapes in a disk-like directory structure.

- If an archive has been lost it is much more painful to find out what is on the tape. I have been shown the process through terminal, but comparing this to just popping the tape in is pretty painful.

Unlike with the Quantum, all your content is fully searchable at any time without the tape even having to be present.

- When I used to back up anything to my LTO3-A-Series, technically all I needed was the tape. Now I need paperwork to go along with it that states the Archive ID, Buffer Size etc.. and also a disc or usb key that will hold the actual Archive folder.

- And then once I deliver a tape with all of the paperwork and disc and or usb key I then have to (or at least should in my best interest) keep all of that on file in my office.... Versus just sending them the tape and if they ever came back all I would need is the tape.

Like the Quantum, a Cache-A system is needed to read the Table of Contents on our tapes. That's the only proprietary file on our systems and then only because, while there is a standard for writing on tape (Yes Jeff, tar is a universally accepted tape format), there was no standard for indexing content. Now that IBM and HP are supporting a standard tape indexing system called LTFS, we will be offering LTFS compatible tape capability in future versions (FYI, this is an LTO-5 only standard).

Many people have set up backup systems that do everything the A-Series does and more, using off the shelf solutions. The A-Series seems convenient at first, but there's really nothing special about it. There are tons of Java / web based front-ends out there that can be hosted on a backup server system and interfaced with your backup software, which will give you everything a Cache-A can do and more.

What is special about our systems is indeed nothing more than convenience but I would assert that it goes much further than surface-level. The convenience of a web UI, the convenience of a pre-configured user-friendly SQL database of all your archives, the convenience of a networked share where any client can dump stuff to be archived, the convenience of being able to directly connect hardware to be archived or to network connect client shares to be archived, the convenience of not having to source, build, test, and maintain all the bits and pieces it takes to create an archiving solution and the convenience of having a live support engineer on call if you are having problems.

I very much doubt even a talented computer expert could put together all these capabilities from off-the-shelf bits and pieces. Even were it possible, how much time would it take? If you enjoy tinkering with computers, don't buy a Cache-A. If you want a tool to archive, ready to go, with support, I think we offer a reasonably priced solution.

 

[ryan schnizlein]

$2.5k archive appliance?

$2.5k archive appliance?

let me start by saying that i feel the cache-a systems are worth their price tag when you look at the features that they provide and the amount of work that has gone into them.

Cache-A here. I'd like to respond to a number of items in this thread...

I very much doubt even a talented computer expert could put together all these capabilities from off-the-shelf bits and pieces. Even were it possible, how much time would it take? If you enjoy tinkering with computers, don't buy a Cache-A. If you want a tool to archive, ready to go, with support, I think we offer a reasonably priced solution.

although i agree with this statement, i wonder if users out there would be interested in a simplified archive appliance under the $2.5k price point (under $4k with bundled drive)? to be clear it would not include all of the features of a cache-a product, which i find extremely useful for a facility. it would simply allow you to connect CF/USB/eSATA storage and archive it to an LTO tape as a standalone appliance. i would use the tar format to keep compatibility.

i apologize if this is not the correct forum to be asking this question.

 

[SCOTT HORTON]

Hi guys:

Sorry to resurrect this old thread. I used to be a regular BRU user, so I'm comfortable wiht he software. I'm interested in a DIY LTO3 or LTO4 backup appliance. I understand LT0-4 may not be practical over GigE (from comments in another thread). I can live with LTO3 for now.

In some other thread someone linked to a place here where someone apparently showed one method to set one up. Does anyone have any pointers to a how-to on building one of these? The Cache-A is attractive, but it's out of my budget. Ebay drives and time to build is OK with me.

Thanks!
Scott

 

[Jeff Kilgroe]

It is correct that Quantum has stopped their A-Series and Cache-A is offering a newer system with LTO-4 and LTO-5 tape drives. I take issue that they are terribly overpriced - at $7k for our Prime-Cache system, you don't save much by building your own solution with off-the-shelf software such as Bru or Retrospect if you include the cost of the host computer.

Of course it's up to each person making the purchase to decide how the pricing works for them. I have no intention of getting into a debate over what can be assembled for what price, on that matter I'll just choose to respectfully disagree and leave it at that.

But as you rightly point out, unless you're comfortable with tinkering on your systems and mixing and matching hardware solutions, the Cache-A does provide a level of convenience or assurance of it working properly and it includes support.

This is completely untrue. Our format on tape is standard unix/linux tar and anyone can read tapes made in one of our systems with any tar capable system. We do indeed have customers successfully sharing Cache-A archived content with non-Cache-A recipients. A technical brief of how to read our tapes is posted on our support page. We make extensive use of tar's capabilities to assure robust and compatible archiving.

I stand corrected then, but must say this is a new development to some extent. I'm aware that the format was claimed to be Unix tar based, since about March of last year when you guys were announcing the LTO-4A products. However, I had always been told up to that point by various people at Quantum, including yourself I believe, that the 3A tapes were proprietary and could only be read in an A-series tape system. Around the time the first LTO-4A units started shipping later last year, I inquired again about the data format and was once again told the tapes were only readable in an A-Series unit.

Specifics on how to access the data was originally not made public, primarily when the system was still within the grasp of Quantum. In fact, that was one of the biggest reasons I did not buy into the 3A system from Quantum in 2008 and did not buy into an LTO-4A later last year. More so with the older 3A unit, as with Quantum's offerings, there seemed to be little assurance of the A-series longevity and no outward intention of making the data format known. The tar based format didn't make itself known until 2009 and only as an extension to whatever Quantum IP was retained and only for use in the new LTO-4A systems. For the tar data recovery, the data block size detail is pretty important -- how many attempts was one expected to try before giving up? Typical sizes are multiples of 16 or technically 128 (256, 512, 1024). 300? Guessing the block size is like trying to guess a forgotten PIN number at an ATM.

Several of us asked for specifics, which really are minor, such as data block size, but no specifics were ever willingly given in the past. Out of curiosity, when was this info actually released? I see the current document is only 3 months old. Last November, I did a write-up about your LTO-4A and worked with a unit owned by another local production company. At that time I inquired <again> and was told then that the format was proprietary and there was <still> no way to read it on anything but an A-Series unit.

Can LTO-3A tapes created with a Quantum A-Series unit be read the same way in any such system with tar tools? Or are they still "special"?

In some other thread someone linked to a place here where someone apparently showed one method to set one up. Does anyone have any pointers to a how-to on building one of these? The Cache-A is attractive, but it's out of my budget. Ebay drives and time to build is OK with me.

Scott, you're right in that Gig-E can be a bottleneck to some of the faster LTO-4 tape mechanisms. Your top realistic speed over Gig-E is about 80~90MB/s. That is respectable, but some LTO-4 systems can write at up to 120MB/s. I wouldn't worry about it too much, it's still a usable connection for offloading data to LTO-4.

That said, what are you looking to build exactly? If you're already familiar with BRU, then I guess I'm wondering if you just want to add an LTO-4 unit to an existing system or what? There's several threads around here on the topic. The preferred LTO-4 stand-alone drive is the HP unit. It comes in a half-height model that can write at up to 80MB/s or a full-height model that can do the 120MB/s. Both available as internal or external desktop variants. Since you're talking about BRU software, that implies connecting the LTO to a Mac. In that regard, the ATTO SAS controllers are the best (and really the only) option. Which one to choose depends on what else you want to use it for -- such as attaching a RAID or eSATA devices, etc.. Cheapest Mac LTO-4 solution that I trust is the HP LTO-4 1760 desktop with an ATTO H380 SAS PCIe card.

 

[Erich Ocean]

Thanks for sharing Jeff, this is useful stuff.

 

[Tom Goldberg]

...I had always been told up to that point by various people at Quantum, including yourself I believe, that the 3A tapes were proprietary and could only be read in an A-series tape system. Around the time the first LTO-4A units started shipping later last year, I inquired again about the data format and was once again told the tapes were only readable in an A-Series unit. <snip> Can LTO-3A tapes created with a Quantum A-Series unit be read the same way in any such system with tar tools? Or are they still "special"?

Quantum A-Series tapes were and still are "special." They use a variable block size and require some pretty complex software to read them. While Cache-A did license technology from Quantum, we did not use any of it when we actually implemented our product. We preferred to use the open tar standard so that tapes we make can be read by anyone into the future whether we're around or not. You'll notice that we don't use the 'A' designation on our tapes or systems anymore as they are in fact standard.

Several of us asked for specifics, which really are minor, such as data block size, but no specifics were ever willingly given in the past. Out of curiosity, when was this info actually released? I see the current document is only 3 months old. Last November, I did a write-up about your LTO-4A and worked with a unit owned by another local production company. At that time I inquired <again> and was told then that the format was proprietary and there was <still> no way to read it on anything but an A-Series unit.

I am surprised and sorry that you were ever informed that we were proprietary. The Table of Contents (TOC) file we save to each tape is the only proprietary thing about what we write, and it is not needed to restore a tape, only to restore individual file(s) or directories.

It did take us a while to get the technical briefs written but it has always been our intent to be open and we should have always freely admitted that we were using tar format. I apologize if we were not forthcoming with any information when you inquired. The blocking factor we are using with our products is 300. I encourage you or anyone reading this to let me know if you have further questions - I will do my best to answer openly.

 

[SCOTT HORTON]

Scott, you're right in that Gig-E can be a bottleneck to some of the faster LTO-4 tape mechanisms. Your top realistic speed over Gig-E is about 80~90MB/s. That is respectable, but some LTO-4 systems can write at up to 120MB/s. I wouldn't worry about it too much, it's still a usable connection for offloading data to LTO-4.

That said, what are you looking to build exactly? If you're already familiar with BRU, then I guess I'm wondering if you just want to add an LTO-4 unit to an existing system or what? There's several threads around here on the topic. The preferred LTO-4 stand-alone drive is the HP unit. It comes in a half-height model that can write at up to 80MB/s or a full-height model that can do the 120MB/s. Both available as internal or external desktop variants. Since you're talking about BRU software, that implies connecting the LTO to a Mac. In that regard, the ATTO SAS controllers are the best (and really the only) option. Which one to choose depends on what else you want to use it for -- such as attaching a RAID or eSATA devices, etc.. Cheapest Mac LTO-4 solution that I trust is the HP LTO-4 1760 desktop with an ATTO H380 SAS PCIe card.

Jeff:

I'm familiar with BRU from several years back when I used it for a completely unrelated thing. We used it to backup some ISP servers that stored user data (mail etc.). I don't do that or use it any more, havent' for years. I thought they went out of business actually.

What I need now is a solid, reliable, shelvable, unmonitored, no fuss backup method. It's for mainly personal use, but I have tons of video and photos I want to backup. If I ever lost any of it, there woudl be hell to pay. My wife takes thousands of photos and I'm happy to eat a fairly expensive solution (not a new LTO-5 if I can avoid it ), becasue it will be less painfull in the long run. I've lost drives several times and thank god I had backups when I did. I've been teh HD ercovery route once, no fun either.

So for my new backup solution I staretd down the multiple hard drive route, but then got worried about shelving them. Personal experience with failures, plus the horror stories you can read on the reseller reviews (i.e. newegg) makes me leery of that as a secure method. Expecially since it's so common to see them fail these days. I have a DAT DDS3 drive now but it's just not big enough (capacity) so I started looking at the LTO drives recently. Used, or open box LTO-3 are reasonable and are reasonably close to OK size for my backups. I have a couple hundred (and counting) DV tapes I'd like to backup. But those can be a do it once and forget it for years (I envison) thing. I don't need anything particularly fast, I do need long term reliable storage. And I'd like to get something large enough (LTO-3 just barely OK) that I won't have to span tapes, but can still get a decent amount onto one tape.

So all that said I looked at internal LTO, but my motherboard won't support a SAS cards so I hit the upgrade domino effect. Which is a roadblock right now. That led me to the A-series device which looked like a really easy solution that I could use, and as my PC's change over time it would be more independent of the desktop(s) as it's on the network.

I'm not a PC expert, but I know enough to build a Linux or Windows PC and deal with hardware. So if it's something that's doable on my own, I'm not afraid to try it. Particularly if I can essentially copy someone elses work.

I've been burned inthe past from having old software issues and the inability to restore from tapes so the less propriatary the better. I currently use XP's ntbackup utility just becasue it's ubiquitous and easy to obtain/install/use. I had a really big problem once with Tapeware that had expired (EOL) and I couldn't get support loading it on modern hardware, or old hardware for that matter. Just about got burned that time. The Yosimite (IIRC) people REALLY ticked me off then.

And suggestions, thread pointers, opinions for a suitable backup method would be most appreciated. I came here partly becasue of the LTO discussions, but becasue I know you guys must have to deal with this issue regularly.

Best,
Scott
www.techht.com

 

[SCOTT HORTON]

What about the Series A LTO3? I understand it's proprietary. I have an opportunity to get one reasonably, but if it were to fail, how would one read the tapes?

 

[Vinit Borrison]

Hey Guys,

What BRU commands can you use in terminal to restore the tape - and all you need is a PDF file that has all the relevant info of what's on the tape?

 

[Tom Goldberg]

What about the Series A LTO3? I understand it's proprietary. I have an opportunity to get one reasonably, but if it were to fail, how would one read the tapes?

Scott, there is no way to read Quantum A-Series tapes without their hardware. Cache-A may implement back-reading at some point in the future, but it is a difficult software effort even with their secret sauce.

If you're not making many tapes and take care of the hardware, it is likely to last until a better alternative comes along, but you will want to migrate your data to something else as soon as you can to be safe.

I suggest you'd be better off sharing the cost of an archiving solution like ours amongst a group if you don't need to archive very often. As we write in tar format, our tapes will be readable long into the future with commodity hardware.

 

[Jesse Korosi]

Hey Guys,

What BRU commands can you use in terminal to restore the tape - and all you need is a PDF file that has all the relevant info of what's on the tape?

Hey Vinit,
If by chance your message means you just received a tape with no archive file and you are looking to retrieve the tapes information through terminal instead of something along the lines of Bru Software. This can indeed be done, but it isnt exactly the easiest task to complete. When I first started working with Bru I had one of the tech's walk me through the procedure and there was no way I was remembering the command lines off by heart. So I took notes, but unfortunately do not have those on hand right now. I am not sure if the terminal was using my Bru software to actually make the pull or not, but either way I am sure they could help you if you give them a call and or what ever companies software you normally run for pulling data.
You will have the option to pull the whole tape or single files.

Cheers,
Jesse Korosi