If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
No S.M.A.R.T. with USB - and with FireWire?
HD in a USB external box = no way to read the S.M.A.R.T. parameters
Anybody knows if S.M.A.R.T data is readable with an external FireWire box? |
#2
|
|||
|
|||
No S.M.A.R.T. with USB - and with FireWire?
M.Riccardi wrote:
HD in a USB external box = no way to read the S.M.A.R.T. parameters Anybody knows if S.M.A.R.T data is readable with an external FireWire box? No, because it is an IDE protocol. |
#3
|
|||
|
|||
No S.M.A.R.T. with USB - and with FireWire?
thank you
On Tue, 25 Oct 2005 15:04:30 +0200, Marc Marc*dot*hulsebosch*at*gmail*dot*com wrote: No, because it is an IDE protocol. |
#4
|
|||
|
|||
No S.M.A.R.T. with USB - and with FireWire?
"M.Riccardi" wrote in message news thank you On Tue, 25 Oct 2005 15:04:30 +0200, Marc Marc*dot*hulsebosch*at*gmail*dot*com wrote: No, because it is an IDE protocol. And if the drive is IDE, and the USB or Firewire is providing an IDE interface, why doesn't it work? |
#5
|
|||
|
|||
No S.M.A.R.T. with USB - and with FireWire?
In article iNZ7f.309160$1i.118446@pd7tw2no, "Noozer"
wrote: "M.Riccardi" wrote in message news thank you On Tue, 25 Oct 2005 15:04:30 +0200, Marc Marc*dot*hulsebosch*at*gmail*dot*com wrote: No, because it is an IDE protocol. And if the drive is IDE, and the USB or Firewire is providing an IDE interface, why doesn't it work? There is a hint on this page. It basically has to do with how "transparent" the bridge chip is, within the enclosure, and whether the protocols being used, have extensions to allow the S.M.A.R.T command to pass. The bridge basically only has to support "read" and "write", to be considered a success. The SCSI command set is frequently used to talk to non-ATA storage devices, and so both the hardware devices and SCSI command interface, need to have the same commands as exist on an ATA device. ******* http://smartmontools.sourceforge.net...ools_scsi.html SCSI disks What is a SCSI disk? A SCSI disk is a storage device that "talks" the SCSI command set. An ATA disk is a storage device that "talks" the ATA command set. That seems pretty clear. However by the time an operating system sees the device the situation can be more complicated. The ATA command set is used over native ATA transports which are parallel ATA (PATA) up to 133 MB/sec and serial ATA (SATA) up to 1.5 Gbps (approximately 150 MB/sec). In the past when ATA disks needed to use some other transport (e.g. USB and IEEE1394) the SCSI command set was sent over the foreign transport. So in this case the operating system sees a device "talking" the SCSI command set but the device is really an ATA disk. Many current disk external enclosures contains ATA disks yet seen from the operating systems view point are USB mass storage devices talking the SCSI command set. The SCSI command set is used over various transports: the SCSI Parallel Interface (SPI), Fibre Channel (FCP), Serial Attached SCSI (SAS), IEEE1394 (SBP) and USB (mass storage). Many of these transports can convey multiple command sets (i.e. not just the SCSI command set). The forthcoming SAS transport is interesting as it can convey both the SCSI and ATA command sets. There is also the case of a RAID made up of ATA disks which communicates to host operating system with the SCSI command set (e.g. 3ware RAID controller). So what does all this mean for smartmontools? In most cases the answer is not good news. Devices such as USB external disk enclosures translate incoming (from the host) SCSI commands to their ATA equivalents and process responses as required. This translation is limited typically to a small number of SCSI commands (e.g. READ and WRITE) but not those commands needed by smartmontools. The author does not know of any SCSI_over_USB devices that support Smartmontools. The 3ware RAID (6000, 7000 and 8000 series Escalade) controllers are supported on several operating systems with special code. [1] SMART SMART never attained the status of "standard" and its original documents have been withdrawn. Its catchy name lives on, especially on vendors' web sites and obviously in the name of this toolset. Luckily the good ideas in SMART have been incorporated into the ATA and SCSI standards albeit in slightly different forms. Initially SMART began on SCSI disks as vendor specific extensions. Gradually the SMART functionality has moved into the standards (often by other names) and vendors are improving their standards' compliance. [In the vendors' defence some of the "standards" are drafts and are yet to be ratified.] Some SCSI disk vendors have product manuals (available on the net) that cover the parts of the SCSI command set that their disk supports. Some of these manuals fill in details that are left deliberately vague in the the standards. [2] SCSI standards (found at www.t10.org ) only make one footnote reference to the term SMART. Instead the awkward term "Informational Exceptions" is used. For SCSI tapes the term "TapeAlert" is used. ******* Paul |
Thread Tools | |
Display Modes | |
|
|