Symantec Drive Encryption: How to find the sector byte size


Article ID: 157255


Updated On:


Drive Encryption


Currently, Symantec Drive Encryption (previously PGP Whole Disk Encryption) is compatible only with 512-sector size and not 4K Native sector size drives. If the drive supports 512 byte emulation mode (commonly referred to as 512e or Advanced Format) then Symantec Drive Encryption should be compatible with the drive.



Each of these commands will be ran in a command line windows in order to help identify whether a drive is using 4K Native, or 512/512e:


Windows Platforms:

Command 1:
Start > Run > cmd and hit enter.

wmic partition get BlockSize, StartingOffset, Name, Index

Sample output from the above command: 
BlockSize  Index  Name                         StartingOffset
512            0         Disk #0, Partition #0  1048576

The above output indicates the drive is either 512, or 512e, both of which can be encrypted.

Command 2:
This command will provide more details as to disk sector size as well as cluster size and free cluster space.

fsutil fsinfo ntfsinfo c:  (or disk letter you want to check.)

Sample output from the above command:

NTFS Volume Serial Number :       0x0c2283282283163c
Version :                         3.1
Number Sectors :                  0x000000002542cec0
Total Clusters :                  0x0000000004a859d8
Free Clusters  :                  0x000000000424ddac
Total Reserved :                  0x0000000000000b50
Bytes Per Sector  :               512
Bytes Per Cluster :               4096
Bytes Per FileRecord Segment    : 1024
Clusters Per FileRecord Segment : 0
Mft Valid Data Length :           0x00000000053ec000
Mft Start Lcn  :                  0x00000000000c0000
Mft2 Start Lcn :                  0x0000000000000002
Mft Zone Start :                  0x00000000000c53e0
Mft Zone End   :                  0x00000000000cc820<:computercode>

If either the "BlockSize" (1st command) or the "Bytes Per Sector" (2nd command) return a value of 4096, the drive has a 4K Native sector size and will not be supported by Symantec Drive Encryption (previously PGP Whole Disk Encryption).  In both of these examples, the operating system interprets this as a sector size  of 512, which can be encrypted.
Macintosh Platforms:
1. Open Terminal (Press the Command Key + Spacebar to open Spotlight, and type "Terminal", and press enter.
2. Run the following command:
diskutil info / | grep "Block Size"
If "Device Block Size: 512 Bytes" is returned, this indicates the drive is using 512.  A value of 4096 Bytes would indicate 4K Native is being used, which cannot be encrypted.
For more information on Symantec Drive Encryption and 4k Native Drives, please see article TECH200098.