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I would like very much if someone would introduce a tape drive with an USB interface, using the USB-Attached-SCSI-Protocol.

This would have no importance for software, as the tape drives would continue to be seen as SCSI devices. The performance of USB is adequate and an USB tape drive could be cheaper, while also saving money for not needing a SCSI HBA.

Unfortunately, there are no tape drives for modern tape standards with USB and no hope that one will appear soon.

I use a tabletop tape drive. Internal tape drives are a little cheaper, but I think that the external drive is more reliable, because it is protected from dust when not active and it is well cooled (even if it is noisy) when it is active.

Previously I have used a SCSI HBA card for PCIe, together with an external SCSI cable having the appropriate connectors.

The server motherboard that I am using now has on-board SCSI, so I have a cable from motherboard to the case, having internal SCSI connectors at one end, to plug in the motherboard, and external connectors at the other end, in a cover for a the opening of an expansion card slot on the case. Then I have an external SCSI cable to connect the tabletop drive.

With SCSI cables, you must pay attention to the connectors at each end, because there are many variants. On the motherboard I have internal high-density connectors, on the case I have external high-density connectors, while on the tape drive I have external lower-density connectors.

I have used 2 kinds of SCSI HBA cards, some with LSI controllers, e.g. LSI LSI00343 SAS 9300-8E Host Bus Adapter, and a similar card with a Microsemi controller (now Microchip). There were no differences, all were OK.

The SCSI HBA cards may have either external connectors or internal connectors or both kinds, so you must choose the appropriate card, depending on whether your drive is internal or external.

The only difficulty that I had in the past was that on some motherboards the computer did not boot with the SCSI card inside and I could not understand why.

I have even bought a second SCSI HBA card from a different vendor, wrongly believing that it is buggy.

The problem turned out to be not a bug, but a standard feature :-(

When booting in legacy mode, some add-in cards, including all SCSI cards and all GPUs, attempt to map their ROMs adding BIOS functions in the address space above 640 kB but under 1 MB, which is accessed in the Intel real-address mode.

The SCSI cards do this for the case when you will attach a HDD or a SSD and you would want to boot from it, which the MB BIOS does not know how to do.

On the computers that refused to boot, without any errror message, I also had a NVIDIA GPU. The sizes of the SCSI ROM with the NVIDIA ROM together exceeded the reserved address area mappable by the BIOS, so the BIOS failed to initialize the GPU. When either one of the 2 cards was present booting was OK, with both cards the computer remained stuck with a blank screen.

The solution for those cards to work together was to go in the BIOS at PCIe properties, select the slot where I intended to put the SCSI card and disable the mapping of the extension ROM.

However, not all BIOSes have these options. On one of my Supermicro MBs, the BIOS had the option, but it did not have any effect, due to a BIOS bug. While I have been very content with the hardware of my Supermicro motherboards, I have encountered a lot of bugs in their BIOSes.

Because I use the HBA only for tapes, disabling the ROM has no consequence, because I never want to boot from SCSI.