4tb internal drive?

Yay details :) mount --bind and ln commands have already been covered on the forum, its quite simple really.

still im intrigued how I am the only person to use a 4tb usb drive when all it takes is a standard ext3 format.
but if the humax is using a kernel which apparently doesn’t cover drives over 2tb then how is it possible I can use the full drive size without any partitions?
 
The Humax doesn't support GPT/GUID/EFI disk partition tables, just MBR. MBR partition tables use 32 bits to store logical block addresses and size information so, for hard disks with 512-byte sectors (physical or logical), you're limited to 2TiB.

In general, even the new AF disks with 4KiB sectors report a 512 byte logical sector size and so share the same limit when a MBR partition table is used.

However if you format with 4KiB sectors then you can go up to 16TiB. There is a chance that the Humax could be made to work with a disk formatted like this but it might involve some work.
 
af123 said:
There is a chance that the Humax could be made to work with a disk formatted like this but it might involve some work.
Click to expand...

its not a chance that it may work, there is no extra work involved, simply format with ext3 4kb and it works. I have been running my 4tb usb drive successfully with the humax for 6 months including direct recording to it.
 
Perhaps this should be in a new thread? To me direct recording from to a USB drive is interesting because it might be made to work on a HD-FOX in HDR mode. I know there are other issues (front panel display, lack of DLNA server, recording with a single tuner) that might prevent a HD-FOX being used like a HDR-FOX, but it is a step forward.

Another nice feature would be the option to decrypt onto an external drive. Currently programmes are decrypted via the DLNA server, with the output saved on the internal drive, and the originals moved to the deleted items folder (when undelete is installed). The option to save the decrypted programme onto a USB drive directly, mediated by a flag in Webif, or through Webif>scheduled events, for example is the aim.
 
sohlinux said:
its not a chance that it may work, there is no extra work involved, simply format with ext3 4kb and it works. I have been running my 4tb drive successfully with the humax for 6 months including direct recording to it.
Click to expand...
I'm pretty sure af123 meant for internal use.
 
My 4TB Seagate Backup Plus external USB hard discs would behave like this report if I connected them to the HDR Fox. The SATA drive inside the enclosure uses 4K physical sectors and operates using 512 byte logical sectors over the SATA interface. This is how most 4K physical sector drives work over SATA and needs a GPT partition table, and slows down unless formatted with the filing system allocation units aligned on 4K boundaries.

BUT, the SATA to USB3 adaptor for this drive does rather more than normal. It presents the drive as 4K logical sectors, bundling eight 512 byte logical sectors at the SATA level into a 4K logical sector over USB. This allows the drive to be supplied MBR formatted with NTFS (I haven't dared reformat it) and as such it works with Windows XP. I believe the drive manufacturers are doing this because otherwise USB hard discs above 2TB wouldn't work when plugged into Windows XP boxes (or similar age vintages of other operating systems) and given the number of XP systems in use no company wants to ship USB drives that don't work with XP.
 
I have an older 2TB Seagate USB drive using the same removable adaptor format. I've never tried it, but I suspect if I put that adaptor on the 4TB drive it would show the 512 byte logical sectors from the SATA interface and the drive would appear to be unformatted in some way.

So this all explains why these drives work externally on USB (whether 3TB or 4TB) when the Humax fomats them Ext3 with 4K logical sectors. But placed internally, suddenly the drives are 512 byte logical sectors and need GPT partition table which the Humax does not support.

Simple really once you know what's going on with the drives. I had to install extra 4K sectors hot fixes from Microsoft to get newer command line tools which print both the logical and physical sector sizes before I was confident of this. I found one forum posting somewhere explaining this, but given it was only one I felt I had to confirm it myself.
 
Black Hole wrote in his "things every... Shoukd know":

"Meanwhile, it has also been reported that some external drives have translation technology built into their USB-to-SATA adapter (internally the physical drive does not come equipped with a USB interface!) so that 512-byte sectors in a GPT structure are presented across the USB link as 4096-byte sectors in an MBR structure - thus rendering the whole of a 4TB drive (or larger) accessible to the Humax operating system:"

Not quite right. There is no GPT structure involved. The USB interface hardware is simply presenting the drive at a low level as a drive full of 4K logical sectors. This then allows it to be formatted by external software on a PC or whatever as an MBR drive because 32 bits worth of 4K logical sectors can access up to 32GB. No GPT anywhere in sight.

There's nothing to stop me formatting this drive as a GPT drive with 4K logical sectors, there just isn't any need. And if I did format it GPT, if the interface were translating GPT to MBR that would cause chaos. The simplest solution is the best in this case.
 
I did indeed mean TB not GB. And yes I got the calculation wrong, I was posting in a hurry before a long drive. The MBR limit with 4K logical sectors is indeed 16GB.

Never mind, we all make mistakes. At least I knew why an external 4TB USB drive worked and an internal SATA one didn't.
 
I read this thread with great interest as I was seeking information on using a 4TB USB disk with my HDR-FOX T2.

Using a WD MyBook 4TB USB drive, I formatted using EaseUS Partition Master - with options MBR EXT3.
Connecting to the HDR-FOX T2 , the disk was loaded with the full 4TB as free.
Copying files from the HDD to the 4TB was as normal.
As expected, the same disk formatted with options GPT EXT3 did not work.:)

Thank for a great forum.
 
af123 said:
The Humax doesn't support GPT/GUID/EFI disk partition tables, just MBR. MBR partition tables use 32 bits to store logical block addresses and size information so, for hard disks with 512-byte sectors (physical or logical), you're limited to 2TiB.
Click to expand...

Since custom firmware 3.00
New custom OS kernel with support for:
  • Large block devices;
  • EFI Partition tables;

Does this mean someone could try a drive larger than 2tb?

EDIT
oops wrong part of the forum, guess this question should be in the custom firmware bit...
 
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