Question Does an LTO drive work on an SAS RAID card ?

[Carl Dempsey]

If not, can anyone tell me a cheap SAS card that WILL work?

TIA.

 

[USAFRet]

If not, can anyone tell me a cheap SAS card that WILL work?

TIA.

An LTO tape drive?
On a 'RAID card'?

Obviously, we need a LOT more information of what you're actually trying to do.

 

[Carl Dempsey]

An LTO tape drive?
On a 'RAID card'?

Obviously, we need a LOT more information of what you're actually trying to do.

An LTO tape drive? YES
On a 'RAID card'? Looking- every card seems to be RAID so need to find a basic card that will work or again - will an SAS RAID card work ?

 

[Misgar]

If not, can anyone tell me a cheap SAS card that WILL work?

Internal or external tape drive?
SAS2 (6Gb/s) or SAS3 (12Gb/s)?
LTO3, 4, 5, 6, 7, 8, 9 ....

I have several ancient SAS3442E (HP SC44Ge Host Bus Adapter) cards in old machines for connection to an external Quantum LTO4 drive. Cheap as chips on eBay (ex-server pulls) but they're PCIe Gen.2 and have only one external SAS port and one internal port (which copes with a full height internal LTO4 drive).

I've got a marginally superior LSI SAS2208 card in this machine.

The remainder of my machines (TrueNAS Core servers) all use IT-mode (Initiator Target firmware) LSI cards, as opposed to IR-mode (RAID firmware). I reflash Dell H200 cards from IR to IT as soon as I buy them. I haven't tried an IR card with LTO.

I measured the transfer rate to my LTO4 drives and it's a constant 80Mbytes/second (native uncompressed 800GB) so the PCIe Gen.2 cards are more than capable. If you're running higher capacity LTO5, 6, 7, etc. you'll need higher sustained transfer rates to avoid 'shoe shining'. This might require a PCIe Gen.3 card.

https://en.wikipedia.org/wiki/Linear_Tape-Open#Generations

Format	LTO-1	LTO-2	LTO-3	LTO-4	LTO-5	LTO-6	LTO-7	Type M (M8)[Note 1]	LTO-8	LTO-9	LTO-10
2000[16]	2003	2005	2007	2010[17]	Dec. 2012[18]	Dec. 2015[19][20][21]	Dec. 2017	Sep. 2021[22]	May 2025
100 GB	200 GB	400 GB	800 GB	1.5 TB[23]	2.5 TB[24]	6.0 TB[21][25]	9 TB	12 TB[26]	18 TB[27][23][14]	30 TB
200 GB	400 GB	800 GB	1.6 TB	3.0 TB	6.25 TB	15 TB	22.5 TB	30 TB	45 TB	75 TB
20	40	80	120	140	160	300[28]	360	400	400
1:23	1:51	3:10	4:20	5:33	8:20	9:16	12:30	20:50
Yes, "2:1"	Yes, "2.5:1"
No	Yes	No [29]	Yes
No	Yes
No	Yes
1 (no partitioning)	2	4

[th]

Release date​

[/th]​

[th]

Native capacity (uncompressed)​

[/th]​

[th]

Advertised capacity (compressed)​

[/th]​

[th]

Max speed MB/s (uncompressed)
[25][Note 2][Note 3]​

[/th]​

[th]

Time to write a full tape at max speed (hh:mm)​

[/th]​

[th]

Compression capable?​

[/th]​

[th]

WORM capable?​

[/th]​

[th]

Encryption capable?​

[/th]​

[th]

LTFS capable?​

[/th]​

[th]

Max. number of partitions​

[/th]​

Maximum uncompressed speeds valid for full height drives. Half height drives may not attain the same speed. Check manufacturer's specifications.

• Previously unused LTO-7 tape, not an independent generation, part of LTO-8 generation. See: Compatibility
• This speed is the data transfer between the drive and the tape. If compression or decompression is being performed, the speed between the drive and the computer writing or reading data could be higher.

This list on Serve The Home gives a large number of LSI card options to investigate:
https://external-content.duckduckgo...27bf8043e4eaaa4bc4d9ffa1e77dfe2739c2e1bacc109

If your tape drive is external, you'll need a cable that matches the drive to the card. I have two different cables for use with two different SAS card connector types.

 

[Misgar]

Could you share a bit more about what system or setup you're trying to use the SAS card with?

Multiple systems (at least 10) comprising a motley assortment of motherboards and Intel/AMD processors, ranging from an ancient AMD FM2 X4 760K up to a 7950X. It doesn't matter what mobo you use, provided it has a slot long enough to hold the LSI SAS card.

Operating systems include Windows 10 Pro and TrueNAS Core. No need to go searching for a driver. Both OS recognise the SAS cards and load a driver automatically.

I run some of my LSI cards in PCIe x16 slots with only 4 lane capabilty, despite the card really needing PCIe x8 (8 lanes). Most of my motherboards restrict the number of PCIe lanes on the secondary and tertiary to x4 or x8, with x16 lanes on the first slot only (closest to the CPU).

The LSI cards run quite happily on 4 lanes, but obviously with only half the already limited bandwidth of Gen.2 or Gen.3 cards. This doesn't matter when all I'm trying to control is an external LTO4 tape drive at 80MB/s transfer rate.

For large multi-drive RAID-Z2 arrays, I put the SAS card in the primary x16 slot and for the full x8 bandwith. I don't need a GPU card in my TrueNAS servers, but instead rely on the iGPU in the CPUs.

I have four TrueNAS Core RAID-Z2 servers. Two in HP ML350P Gen.8 servers and two in ancient AMD desktops. Three of the four servers each contain 8 hard disks, the other only 6.

LSI "-8i" SAS cards are ideal for augmenting the limited numeber of SATA ports on some motherboards, although I do have two other systems (Phenom II X4 and Xeon) with 10 on-board SATA ports. If you need fewer ports, buy the "-4i". If you need more, buy the -12i, -16i or -20i variants.

I have 8 SAS drives in one server and 8 or 6 SATA drives in the other three. You cannot mix SATA and SAS drives on the same controller. Stick to one interface per card.

As mentioned earlier, I reflash any IR cards to IT-mode, because TrueNAS Core is software RAID and needs full "visibility" of the hard disks. A hardware RAID card (IR-mode) hides important disk information/control capability, making it difficult to set up a software array in TrueNAS.

I run RAID-Z2 in all my servers (equivalent to RAID6). This means I can (in theory) lose any 2 drives and my data should still be "safe". In practice, if two drives fail, I might expect hidden problems on a third drive to surface during resilvering which is bad news. That's why I keep numerous backups on multiple systems and tape.

In some machines, I do not have any external SAS ports on the controller card. These cards are purely to control multiple internal hard disks. In other systems, the SAS card is for the external tape drive and I don't use any internal SAS ports.

You can use the LSI card (IT-mode) without RAID, e.g. on Windows 10, all the hard disks connected to the SAS controller are visible as individual drives. No different from connecting the drives to the on-board SATA ports, except you can use server SAS drives instead of SATA.

When choosing a card, keep in mind the number and type of ports required, i.e. internal and/or external.

Then there's the connector type/termination to consider.

I use 'SFF-8087 to SATA' or 'SFF-8087 to SAS' Forward Breakout cables for hard disks with my more "modern" cards. Do not buy the Reverse Breakout cables by mistake.

The older SAS3442E style card needs an SFF-8484 breakout cable for hard disks. I have an internal LTO4 drive connected to a SAS3442E card using a dedicated SFF-8484 lead.

Check the external port connection carefully. I have two different cables for my external Quantum LTO4 drive, because my various SAS cards have different connectors on the bracket.