How to Determine Oracle Solaris Support for Advanced Format Disks

by Raoul Carag and Cindy Swearingen

This article summarizes the advanced format disks that are supported by various Oracle Solaris releases and how to identify the different types of disks.


Published October 2014


Previous Oracle Solaris releases support disks with a physical block size and a logical block size of 512 bytes. This is the traditional disk block size that is an industry standard. These disks are generally known as 512n disks for 512 native devices.

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Currently, disk manufacturers are providing larger capacity disks known as advanced format (AF) disks, which is a general term that describes a hard disk drive that exceeds a 512-byte block size.

AF disks are generally in the 4-KB block size range, but vary as follows:

  • 4-KB native disk (4kn)—Has a physical and logical block size of 4 KB
  • 512-byte emulation (512e)—Has a physical block size of 4 KB but reports a logical block size of 512 bytes

Current Oracle Solaris releases support 512n disks as well as AF disks.

Identifying an AF Disk's Type

The following examples show how to identify the logical block size and the physical block size of a specified disk, which in turn, identifies whether the disk is 512n, 512e, or 4kn.

The output of the following command identifies the device as a 512n disk.

# devprop -n /dev/rdsk/c2t5000C5001019EBABd0 device-blksize device-pblksize
512
512

The output of the following command identifies the device as a 512e disk.

# devprop -n /dev/rdsk/c2t5000C50010199F2Fd0 device-blksize device-pblksize
512
4096

The output of the following command identifies the device as a 4kn disk.

# devprop -n /dev/rdsk/c2t5000C50010198513d0 device-blksize device-pblksize
4096
4096

Identifying the Supported AF Disks for Your Environment

When you consider purchasing AF disks for storage on your Oracle Solaris systems, review the following tables to see which disk type is appropriate for your environment.

Table 1. Support for AF Disks as Non-Root Devices
AF Disk Type File System/Volume Manager Oracle Solaris 10 1/13 Oracle Solaris 11 11/11 Oracle Solaris 11.1 Oracle Solaris 11.2
512e ZFS Yes Yes Yes Yes
UFS Yes with performance penalty Yes with performance penalty Yes with performance penalty Yes with performance penalty
SVM Yes with performance penalty Yes with performance penalty Yes with performance penalty Yes with performance penalty
4kn ZFS Yes Yes Yes Yes
UFS No No No No

Table 2. Support for AF Disks as Root Devices
AF Disk Type Platform Oracle Solaris 10 1/13 Oracle Solaris 11 11/11 Oracle Solaris 11.1 Oracle Solaris 11.2
512e SPARC UFS; ZFS ZFS ZFS ZFS
x86-UEFI N/A ZFS ZFS ZFS
x86-BIOS UFS; ZFS with GRUB patch 15810943 ZFS ZFS ZFS
4kn SPARC ZFS with OBP 4.34.x and later ZFS with OBP 4.34.x and later ZFS with OBP 4.34.x and later ZFS with OBP 4.34.x and later
x86-UEFI N/A No No ZFS
x86-BIOS No No No No

See Also

About the Authors

Raoul Carag is a senior technical writer at Oracle.

Cindy Swearingen is an Oracle Solaris Product Manager who specializes in ZFS and storage features.

Revision 1.0, 10/17/2014

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