If you don’t have a computer with PCIe expansion slots – there are no easy and inexpensive ways of attaching an LTO tape drive to it.
For quite some time now I’ve been doing my backups (including all of the content on this website) by Tape. Why? Quite frankly I just like them. If like me you buy older generation drives second hand for personal backup, I find it actually works out cheaper than having say, two or three (or more) USB hard disks. The low cost of the media also allows me to have a history of my data (say, a copy from each year), because sometimes, things get lost or corrupted, I don’t realise it, then end up overwriting a good (backup) copy of data with bad (or no) data.
There are other significant benefits of tape – particularly in the robustness and simplicity of the media. Tape media is purely mechanical (aside from the RFID chip on the side) meaning that there’s no electronics which can be damaged. The physical spool of tape is also very robust, unlike the glass platters of a hard disk.
Dropped your tape and smashed it? Somehow managed to kill that RFID chip? No problem. Just buy another tape, undo the four Phillips screws on the bottom and transfer the tape spool to another shell, and you’re back in business. Good luck doing anything like that on a hard disk!
Happened to be subject to a massive electrical surge or lightning strike while your one and only copy of data on a tape was in the drive? Once again, no problem. Tapes have no electrical connection to the drive whatsoever, even during operation.
When talking about backup, IT administrators often use the term “air gap” meaning that data cannot be wiped out by a virus or other accidental software or power incidents. Tape, today, remains the undisputed the king of air gaps.
LTO Tape drives (these days) come with either Fiber Channel, or SAS interfaces – there are no other options. This makes them a little difficult to attached to (For example) a Mac, or any Laptop. Desktop PCs & Mac Pro’s are not an issue because you’ll likely have PCIe slots where a SAS or Fiber Channel host adapter can be installed.
I don’t actually have any PCs with PCIe slots in them anymore, and haven’t had for quite some time so have had to confront this issue myself.
Before we get into the topic of attaching drives, it may be worth considering the drives themselves – assuming you haven’t already purchased one.
Despite a range of different brands, there are two manufacturers of LTO tape drives: HP & IBM. We can see this in the picture with our top drive having an IBM style blue button like what is found on their servers and desktop PCs, and the bottom drive featuring HP’s corporate font under the LEDs.
Dell models feature a slightly different chassis however they are still IBM drives.
Both are very well engineered as you can imagine for the large price paid for these units purchased new.
There are some things to consider (in the context of tabletop drives) when choosing one over the other:
IBM Tabletop Drive
- Slimmer more aesthetically pleasing design
- Good full featured LTFS implementation for Windows
- Easy single handed tape insertion – like a VCR
- Slightly more pleasing operational noises
- Very robust all metal chassis
- Easy to dismantle (four screws on the underside, cover slides off)
- Extremely noisy high-RPM 40mm fan on rear, always runs and restricts the drive to server room use only
- Annoying high pitched sound when loading tape
- Mine seems to jam during loading about 1 in 20 times – requiring a second attempt (which it does by its self automatically)
- Drive is very long (340mm), may not fit on some shelves
- “Soft” power switch. Power supply is still on even when drive is off
- An extra $1000 for an IBM branded one (grumble)
HP Tabletop Drive
- “Fat” design thermally superior to IBM’s. Uses larger, quieter fan
- Fan is only on when tape is inserted, goes unto standby mode when empty (thanks to a fan output connector on the drive its self) – likely applies to LTO-6 drives and earlier only.
- Shorter than IBM drive (300mm)
- Full AC power switch on front (I think)
- LTFS Implementation for Windows less featured than IBMs (LTO-6 and earlier). Depending on your use case you may also want to supplement it with this.
- Operational noises a little more irritating than the IBM drive
- LTO-6 and earlier drives have a “flap” which has to be lifted up to insert a tape making it a two hand job. If you use the drive a lot – this is going to piss you off.
- Outer plastic chassis not as robust as IBM drive (there is also an inner metal chassis).
- Complicated chassis design must be dismantled in a very specific way to avoid breaking internal plastic clips.
Side note: I have made several references to “LTO-6 and earlier” here. This is because the last generation of drive made by HP was LTO-6. From 7 onward, HP drives are re-branded IBM drives deployed in HP’s traditional black plastic chassis.
Option 1: Adapting SAS to USB
Edit: Since I first published this, it occurred to me that the product I mention below may not be suitable for LTO tape drives. Traditionally USB to SCSI adapters had two modes: “Mass storage” (most common use cases i.e. hard disks / optical media) and “SCSI emulation” (less used devices i.e. scanners and tape drives).
SCSI emulation would also be required to support an LTO tape drive connected via a USB to SAS adapter, as tape drivers require a native SCSI software API to the drive, which “mass storage” mode does not provide. I have not been able to find a detailed specification for the below product, thus it is unclear whether or not it would be suitable for this application. The “No drivers required” claim frequently attached to this product implies that it’s “mass storage” mode only, as SCSI emulation would require specific drivers. Please drop me a comment if you actually happen to have one!
A product: (“CXRT SAS to USB 3.0 Bridge”) appears to exist which converts USB 3.0 to SAS:
Due to the obscene cost, obscurity and that this is not a confirmed solution – I would not recommend going down this path.
Option 2: Native USB drives
There are examples of USB LTO tape drives out there:
A Japanese company Unitex sells a range of LTO tape drives with USB 3.0 interfaces. Pricing is “don’t ask”. I’ve not seen any of these units for sale second hand.
I would guess these units have some kind of proprietary USB to SAS bridging solution developed by the manufacturer.
A solution like the above is sold at such a premium that you would be able to buy a brand new SAS drive, entire Thunderbolt enabled PC or laptop, PCIe enclosure, HBA and cables (all detailed below); with quite a bit of money to spare. For that reason, only appropriate where money is no object, and no other solution is possible.
Option 3: Thunderbolt (buy one pre-made)
If you’re not technical and/or not on a budget, there are a few ready-made Thunderbolt drives. These internally contain a PCIe to SAS host adapter as I demonstrate below. Expect to pay a $2000-3000 premium for this convenience. A product like this uses an ATTO or Highpoint SAS controller which is required for compatibility with macOS X – the primary target market for these products.
Option 4: Thunderbolt (pre-made SAS adapter)
This will be a little cheaper than buying a pre-built drive but still a lot more expensive than the option below. You’ll have to source the appropriate SAS cable. More about that below.
Option 5: Thunderbolt (make your own)
This is a far more sensible (and cheaper) option. Because Thunderbolt carries PCIe we can use (For example) an eGPU enclosure to carry a PCIe SAS Host adapter.
I personally use an LSI SAS9207-4i4e. The LSI SAS9207-8e (two external ports) would also be suitable, as would many others. I have chosen this because it is a fairly recent adapter, which also has the very same SFF-8088 connector found on the tape drive. I got this adapter off eBay for $30.
The full setup
To the left we have a PCIe Thunderbolt enclosure containing the Host Adapter. There are lots of Thunderbolt PCIe enclosures on the market, you can pretty much just pick the cheapest one as a SAS Host Adapter is not a very demanding card to install in one. Single slot enclosures seems to be the cheapest at around $200 at the time of writing.
To the right is the tape drive.
If we go down this path, in addition to only having spent $300 (excluding the cost of the drive), we also have the bonus of having a few new items that have other uses. For one the Thunderbolt enclosure can be used for other PCIe cards, also the SAS Host Adapter can be used as a very high performance connection for SATA hard disks too. There are many different cables and enclosures which can make use of this.
SAS cable selection
SFF-8088 cables come either x1 (one lane) or x4 (four lane) variants. A tape drive only has one lane so either an x1 or x4 cable will be OK. x1 cables are considerably thinner and lighter than x4 cables.
You can also buy fairly long SAS cables too. Bear in mind that tape drives are quite noisy, you may want to consider buying a longer cable (up to 10M / 33ft) so you can put the drive somewhere it’s not going to irritate you.
There are multiple type of external SAS connector presently in use and these days SFF-8644 is beginning to replace SFF-8088 despite it still being common on tape drives. It’s not a problem if you end up having to buy a SAS Host Adapter which has a SFF-8644 connector on it, you’ll just have to buy a cable which has the appropriate connectors on each end.
Operating system (Windows/Linux)
On Windows 10 I did not have to install any drivers for the Thunderbolt enclosure or SAS Adapter – it all just worked.
The only driver I did have to install was for the tape drive its self.
Linux is even easier with all of the necessary drivers built into the kernel.
Operating system (macOS X)
There will not be any driver issues with either the Thunderbolt enclosure or the tape drive – they will work out of the box.
The issue arrives with the SAS host adapter. Unfortunately SAS support is quite poor in macOS with only a handful of ATTO and Highpoint chipsets supported. It is these chipsets which are found in expensive ready-to-go solutions I have previously mentioned.
If you are lucky you might get one on a PCIe card for a decent price. Pictured above is an ATTO ExpressSAS H644 which you conceivably may be able to pick up second hand for a less than bank-balance-busting price but I wouldn’t count on it. Honestly, if you’re an Apple person, it’s likely not worth the hassle for you. Magstor’s $5500 drive will work a treat.
As it happens I do own a Mac, and I’ve managed to pick one of these up for a very reasonable price second hand, so let’s try it out…
The ATTO worked out of the box. I didn’t have to install any additional driver packages. LTFS detected the drive and mounted it just fine. LTFS is a little more difficult to use on Mac than Windows because of the strong mount/unmount concept its Unix-like kernel utilises, for example, after inserting blank a tape, nothing happens.
You have to start the LTFS Manager, format it, and mount it as three separate steps. When finished you then have to start it up again to unmount, and eject the tape, when finished. Another three steps. On Windows, everything can be done from file explorer, with no need for additional steps over say a USB thumb drive.
Since experience the reason you have a Mac, you’re probably going to want to look at some commercial backup software to run your tape drive, which won’t involve any hassle. There are many choices.
I couldn’t find anything to substantiate the claims of other Mac-centric tutorials on this that setting up LTO tape drives is easier on Mac. It’s easy to set them up on both Windows and Mac. The only difference I could see is that on Mac, the solution costs a lot more money.
As was to be expected, my inexpensive LSI adapter wasn’t detected by macOS, nor are there any drivers available for download.
I found that it all works like a charm. You can either hot plug the whole setup through the Thunderbolt cable, or you can just disconnect the SAS cable (or even power off the drive), as SAS is also hot-pluggable, if for example you use your SAS host adapter and PCIe enclosure for other things (as I do).
Fiber Channel instead of SAS
You could also substitute a PCIe SAS adapter for a Fiber Channel host adapter in your Thunderbolt enclosure if that’s the kind of drive you happen to have. You can do your own research on that. This is going to be a lot more complicated but the advantage of this option is that you could have your tape drive a very long way from your PC.
Are SATA adapters of any use?
For the most part, no. If you are starting with a SATA/eSATA controller, there is no way to adapt to SAS. You must start with a SAS controller. SAS controllers however, support either.
There are some scenarios where SATA to SAS/SFF adapters are useful – for example:
Let’s say you have a SAS controller with a bunch of SATA HDDs attached via a SAS to SATA octopus cable, and you happened to have a spare port – it is possible to adapt that port back to SAS, to attach to a SAS tape drive.
Essentially – it doesn’t matter if intermediate the cabling or connectors are SATA, just so long as you have SAS hardware at either end. SAS and SATA cables & connectors are eletrically the same i.e. 2x 100Ω differential pairs each – differing only mechanically.
It also doesn’t matter that you are using a mix of devices on one host adapter – so long as you’re not trying to put those devices into a single RAID volume – SAS controllers don’t care.
Because the tape drive will only be using one port on the SFF-8088 connector, you can connect that one spare SAS port to port 1 on the adapter.
Older laptops with ExpressCard slots
There are some products which adapt ExpressCard to PCIe which would allow a SAS adapter to be attached.
There are some examples of SAS ExpressCard adapters:
Very few true SAS ExpressCard adapters like the above were ever made. None are made anymore and anyone who has one may expect a high price for it.
Most products resembling the above are 4x SATA controllers with an SFF-8088 connectors, which is of no use for tape drives.
Future interface for LTO tape drives?
There is a lurking question about the future of SAS as the primary interface for LTO tapes. Today SAS is effectively dead in the server space (now replaced by NVMe). Tapes aren’t going away anytime soon. Requiring a SAS HBA just for a tape drive will become increasingly unwelcome.
This is actually the situation I am presently in. I have been using LTO tapes to backup for a long time, I’m happy with the solution however my SAS RAID array which used to occupy 6 ports on my SAS HBA has long been retired, replaced by a single M.2 NVMe SSD, leaving behind a large PCIe slot hogging, electricity burning peripheral in one of my servers which is only used to interface with a tape drive once a month.
Frankly, it’s a pain in the backside. Some kind of replacement interface is wanted. Failing that, “Tri-Mode” (SAS/SATA/NVMe) HBAs may be able to give us at least something back for that likely 8x PCIe slot we’re having to sacrifice.