Issues formatting 8TB 512e to 4Kn

FMA1394

Active Member
Jan 11, 2013
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I've done this several times with He8 and He10 SAS 512e drives to get physical and logical units to both be 4096.

However, I have a stack of ST8000NM0075 drives that I'm trying to do this to and keep getting 4224 physical and 528 bytes logical. I've tried:

sg_format --size=4096 --format /dev/sdal
SeaChest_Format_121_1183_64 -d /dev/sdal --formatUnit 4096 --protectionType 0 --fastFormat 0 --confirm I-understand-this-command-will-erase-all-data-on-the-drive

Both result in the bizarre 4224 physical, 528 logical issue.

Any ideas? Drive was initially 4096 physical and 512 logical, but have I effed everything up?
 

FMA1394

Active Member
Jan 11, 2013
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Trying to just go back to 512e and it won't get off of 528/4224. Any ideas?

Tried

sg_format --size=512 --format --fmtpinfo=0 --pfu=0 /dev/sdaj

and no luck
 

FMA1394

Active Member
Jan 11, 2013
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So... maybe I had to do it twice or something, but the drives are coming back now as 512/4096, thankfully.

Lesson learned: HGST He8/He10 512e can be reformatted to 4Kn, Seagate not so much. Check the specs sheet.

I actually had a support case open with Seagate regarding this, and they not only do not support Linux/UNIX, but the drives according to them do not support reformatting to 4Kn. They have some drives that support this, but not EXOS 7E8 512e drives.
 

metag

Member
Apr 26, 2016
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So... maybe I had to do it twice or something, but the drives are coming back now as 512/4096, thankfully.

Lesson learned: HGST He8/He10 512e can be reformatted to 4Kn, Seagate not so much. Check the specs sheet.

I actually had a support case open with Seagate regarding this, and they not only do not support Linux/UNIX, but the drives according to them do not support reformatting to 4Kn. They have some drives that support this, but not EXOS 7E8 512e drives.
Can you share full instructions to format He8 512e to 4Kn? I bought a mix set of 512e and 4Kn by accident. I would love to format them all to 4Kn. Thanks!
 

metag

Member
Apr 26, 2016
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what are the benefit to formating drive to 4Kn logical unit ??
In my case, neither LSI Raid controller nor Windows storage space allows mixing 512e drives with 4Kn drives. So I had to create two separated virtual drives, one for 512e, one for 4Kn, which is not ideal for my setup.
 

Evan

Well-Known Member
Jan 6, 2016
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I don’t think there really is much difference between 512e and 4K

512e already takes advantage of the new ecc codes and you get the same space.
I didn’t notice in the spec sheet any performance difference but that doesn’t mean there isn’t.
 

oxynazin

Member
Dec 10, 2018
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I read on some forums that you cannot change 512e to 4kn. Only exception is when there's manufacturer's utilities for this. But I'm totally confused. Is these He8 and He10 512e drives is totally identical to 4kn drives after sg_format? I downloaded PDF specs for He10 drives, the only difference between them as I can see is format. As I understand, sg_format with size parameter sends SCSI command SELECT MODE which changes block size and after it another command FORMAT UNIT. Is block size from SCSI terminology the same as logical sector size? Does the firmware of 512e drives dynamically emulate sector size for OS depending on the SCSI block size that drive reports to OS? If so then at least these HGST drives can be converted from 512e to 4kn and vice versa. But I cannot understand will be for example HUH7210105200 (manufacturer's format 512e) after "sg_format --size=4096" command totally identical to HUH7210104200 model (manufacturer's format 4kn) or there're some other differences on hardware level or firmware?
 
Last edited:

astrocrab

New Member
Feb 27, 2020
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I've done this several times with He8 and He10 SAS 512e drives to get physical and logical units to both be 4096.
what the secret is?
i'm trying to convert both my sata He10 and He12 to 4kn but i got error all the time

# sg_format --format --size=4096 /dev/sdc
ATA HGST HUH721010AL W21D peripheral_type: disk [0x0]
Unit serial number: -HIMITSU-
LU name: 5000c---------e
Mode Sense (block descriptor) data, prior to changes:
Number of blocks=0 [0x0]
Block size=512 [0x200]
Try MODE SELECT again with SP=0 this time
MODE SELECT command: Illegal request
try '-v' for more information
sg_format failed: Illegal request
 
Last edited:

FMA1394

Active Member
Jan 11, 2013
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Hey astrocab.

Had a chuckle out of "HIMITSU" for serial number. lol.

This is a SAS only thing, not SATA. That's why it doesn't work.
 
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