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While we're here, are there any eHDD standards (and devices) that allow you to plainly read the SATA data from the drive, merely acting as a transport for the S

While we're here, are there any eHDD standards (and devices) that allow you to plainly read the SATA data from the drive, merely acting as a transport for the SATA connector itself? A fair number of them don't allow you to read SMART, for instance (I think this is terrible for a good number of reasons, but alas...) From what I understand, many eHDDs don't actually do this, instead reading the contents of the drive and exposing them to the computer by essentially emulating a USB flash drive. I would have to sniff the packets to be sure, but this is what I suspect my eHDD caddy is doing. My main reason for wanting this is that, in some cases, it would make reading random drives substantially easier -- I have amassed a collection of HDDs that all have different partition schemes, filesystems, etc., and a fair number of those are unable to be processed by my caddy. This is a very frustrating experience, as a Linux device has some of the best filesystem / partitioning support in the world (and a random £15 caddy is obviously not going to provide very good competition.) On the contrary, having the kernel process the HDD as a block device would most likely place it under marginally more computational stress (as opposed to the drive reading partition tables and filesystems itself), but I believe that's been fairly well-optimized by now.

jsheard 3y ago
The standard you're looking for is UASP, which encapsulates raw SCSI commands over a USB connection. Most newer SATA enclosures should support it, they usually mention UASP in the product description if they do, since it has better performance than the older style which emulated generic USB mass storage.
- tentacleuno 3y ago
  Ahh, Hacker News never fails to disappoint. Are there any ones you would recommend? A quick Amazon search yields a ton of rando-name products that I don't place much faith in -- the only brand name I could find was Sabrent[0], but that's only 2.5" and I suspect it's running the drive at 5v. My current one (which I believe is WD) has long since been liberated from its chassis, but it does have a separate 12/2 power supply as opposed to running the drive on the 5v USB connector. On a positive note, I very much suspect the USB-C connector of being miles better than the Micro USB 3.0 interface my current caddy uses. In my experience, a bit of external force can easily encourage the connector out of the port. > (and a random £15 caddy is obviously not going to provide very good competition.) P.S. re this, I can sort of understand it, as the caddy came with a drive -- they clearly had the opportunity to optimize away support for filesystems that they weren't pairing the caddy with. [0]: https://www.amazon.co.uk/SABRENT-enclosure-indicator-tool-free-EC-UASP/dp/B00OJ3UJ2S https://www.amazon.co.uk/SABRENT-enclosure-indicator-tool-fr...
  - jsheard 3y ago
    How about this one from Sabrent? 3.5", USB-B, UASP, external 12v supply. https://www.amazon.co.uk/SABRENT-enclosure-indicator-tool-free-EC-DFLT/dp/B00LS5NFQ2 https://www.amazon.co.uk/SABRENT-enclosure-indicator-tool-fr...
- deleted 3y ago
  [deleted]
- formerly_proven 3y ago
  iirc there are/were still issues because SMART is part of ATA but not part of SCSI so you need an extra encapsulation layer - smartmontools has code to send special vendor-defined packets because of this.
riobard 3y ago
It’s literally called eSATA.
- tentacleuno 3y ago
  Could you please clarify this? I was under the assumption that eSATA was the name for the external [hot-pluggable] SATA connector. If memory serves, eSATAp was that, but combined with a USB plug. Very clever engineering, though the connector seems to be very rare these days (possibly due to SATA itself losing market share [in the context of ordinary people]).
  - riobard 3y ago
    > eHDD standards (and devices) that allow you to plainly read the SATA data from the drive, merely acting as a transport for the SATA connector itself I'm a bit confused, but isn't eSATA exactly what you are looking for?
jonpurdy 3y ago
I went through this exact rabbit hole in 2021 looking to out about USB enclosure CPU usage. As jsheard mentioned, you're looking for UASP. UASP has been around for a decade or more and even the cheapest USB enclosures should support it. I use a Sabrent※ that was $11USD last year. ※ Listed on Amazon as "SABRENT 2.5-Inch SATA to USB 3.0 Tool-Free Clear External Hard Drive Enclosure [Optimized for SSD, Support UASP SATA III]"

jsheard 3y ago

The standard you're looking for is UASP, which encapsulates raw SCSI commands over a USB connection. Most newer SATA enclosures should support it, they usually mention UASP in the product description if they do, since it has better performance than the older style which emulated generic USB mass storage.

tentacleuno 3y ago
Ahh, Hacker News never fails to disappoint. Are there any ones you would recommend? A quick Amazon search yields a ton of rando-name products that I don't place much faith in -- the only brand name I could find was Sabrent[0], but that's only 2.5" and I suspect it's running the drive at 5v. My current one (which I believe is WD) has long since been liberated from its chassis, but it does have a separate 12/2 power supply as opposed to running the drive on the 5v USB connector. On a positive note, I very much suspect the USB-C connector of being miles better than the Micro USB 3.0 interface my current caddy uses. In my experience, a bit of external force can easily encourage the connector out of the port. > (and a random £15 caddy is obviously not going to provide very good competition.) P.S. re this, I can sort of understand it, as the caddy came with a drive -- they clearly had the opportunity to optimize away support for filesystems that they weren't pairing the caddy with. [0]: https://www.amazon.co.uk/SABRENT-enclosure-indicator-tool-free-EC-UASP/dp/B00OJ3UJ2S https://www.amazon.co.uk/SABRENT-enclosure-indicator-tool-fr...
- jsheard 3y ago
  How about this one from Sabrent? 3.5", USB-B, UASP, external 12v supply. https://www.amazon.co.uk/SABRENT-enclosure-indicator-tool-free-EC-DFLT/dp/B00LS5NFQ2 https://www.amazon.co.uk/SABRENT-enclosure-indicator-tool-fr...
deleted 3y ago
[deleted]
formerly_proven 3y ago
iirc there are/were still issues because SMART is part of ATA but not part of SCSI so you need an extra encapsulation layer - smartmontools has code to send special vendor-defined packets because of this.

riobard 3y ago

It’s literally called eSATA.

tentacleuno 3y ago
Could you please clarify this? I was under the assumption that eSATA was the name for the external [hot-pluggable] SATA connector. If memory serves, eSATAp was that, but combined with a USB plug. Very clever engineering, though the connector seems to be very rare these days (possibly due to SATA itself losing market share [in the context of ordinary people]).
- riobard 3y ago
  > eHDD standards (and devices) that allow you to plainly read the SATA data from the drive, merely acting as a transport for the SATA connector itself I'm a bit confused, but isn't eSATA exactly what you are looking for?

jonpurdy 3y ago

I went through this exact rabbit hole in 2021 looking to out about USB enclosure CPU usage. As jsheard mentioned, you're looking for UASP. UASP has been around for a decade or more and even the cheapest USB enclosures should support it. I use a Sabrent※ that was $11USD last year. ※ Listed on Amazon as "SABRENT 2.5-Inch SATA to USB 3.0 Tool-Free Clear External Hard Drive Enclosure [Optimized for SSD, Support UASP SATA III]"