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VDEVPROPS(7)		Miscellaneous Information Manual	  VDEVPROPS(7)

NAME
       vdevprops -- native and user-defined properties of ZFS vdevs

DESCRIPTION
       Properties  are	divided	into two types,	native properties and user-de-
       fined (or "user") properties.  Native properties	either export internal
       statistics or control ZFS behavior.  In addition, native	properties are
       either editable or read-only.  User properties have no  effect  on  ZFS
       behavior, but you can use them to annotate vdevs	in a way that is mean-
       ingful  in  your	 environment.  For more	information about user proper-
       ties, see the "User Properties" section,	below.

   Native Properties
       Every vdev has a	set of properties that	export	statistics  about  the
       vdev  as	 well as control various behaviors.  Properties	are not	inher-
       ited from top-level vdevs, with the  exception  of  checksum_n,	check-
       sum_t, io_n, io_t, slow_io_n, and slow_io_t.

       The  values of numeric properties can be	specified using	human-readable
       suffixes	(for example, k, KB,  M,  Gb,  and  so	forth,	up  to	Z  for
       zettabyte).   The  following  are all valid (and	equal) specifications:
       1536M, 1.5g, 1.50GB.

       The values of non-numeric properties are	case  sensitive	 and  must  be
       lowercase.

       The  following  native properties consist of read-only statistics about
       the vdev.  These	properties can not be changed.

       capacity	      Percentage of vdev space used

       state	      state of this vdev such as online, faulted, or offline

       guid	      globally unique id of this vdev

       asize	      The allocable size of this vdev

       psize	      The physical size	of this	vdev

       ashift	      The physical sector size of this vdev expressed  as  the
		      power of two

       size	      The total	size of	this vdev

       free	      The amount of remaining free space on this vdev

       allocated      The amount of allocated space on this vdev

       expandsize     How much this vdev can expand by

       fragmentation  Percent of fragmentation in this vdev

       parity	      The level	of parity for this vdev

       devid	      The device id for	this vdev

       physpath	      The physical path	to the device

       encpath	      The enclosure path to the	device

       fru	      Field Replacable Unit, usually a model number

       parent	      Parent of	this vdev

       children	      Comma separated list of children of this vdev

       numchildren    The number of children belonging to this vdev

       read_errors, write_errors, checksum_errors, initialize_errors
		      The  number  of  errors of each type encountered by this
		      vdev

       null_ops, read_ops, write_ops, free_ops,	claim_ops, trim_ops
		      The number of I/O	operations of each type	 performed  by
		      this vdev

       null_bytes,    read_bytes,    write_bytes,   free_bytes,	  claim_bytes,
		      trim_bytes
		      The cumulative size of all operations of each type  per-
		      formed by	this vdev

       removing	      If this device is	currently being	removed	from the pool

       The following native properties can be used to change the behavior of a
       vdev.

       checksum_n, checksum_t, io_n, io_t, slow_io_n, slow_io_t
		   Tune	 the fault management daemon by	specifying checksum/io
		   thresholds of <N>  errors  in  <T>  seconds,	 respectively.
		   These  properties  can  be set on leaf and top-level	vdevs.
		   When	the property is	set on the leaf	 and  top-level	 vdev,
		   the	value  of the leaf vdev	will be	used.  If the property
		   is only set on the top-level	vdev, this value will be used.
		   The value of	these properties do not	 persist  across  vdev
		   replacement.	  For  this reason, it is advisable to set the
		   property on the top-level vdev - not	on the leaf  vdev  it-
		   self.   The	default	values for OpenZFS on Linux are	10 er-
		   rors	in 600 seconds.	 For OpenZFS on	FreeBSD	 defaults  see
		   zfsd(8).

       comment	   A text comment up to	8192 characters	long

       bootsize	   The amount of space to reserve for the EFI system partition

       failfast	   If  this device should propage BIO errors back to ZFS, used
		   to disable failfast.

       path	   The path to the device for this vdev

       allocating  If this device should perform new allocations, used to dis-
		   able	a device when it is scheduled for later	removal.   See
		   zpool-remove(8).

   User	Properties
       In  addition  to	the standard native properties,	ZFS supports arbitrary
       user properties.	 User properties have no effect	on ZFS	behavior,  but
       applications or administrators can use them to annotate vdevs.

       User property names must	contain	a colon	(":") character	to distinguish
       them  from native properties.  They may contain lowercase letters, num-
       bers, and the  following	 punctuation  characters:  colon  (":"),  dash
       ("-"),  period ("."), and underscore ("_").  The	expected convention is
       that  the  property  name  is  divided  into  two  portions   such   as
       module:property,	but this namespace is not enforced by ZFS.  User prop-
       erty  names can be at most 256 characters, and cannot begin with	a dash
       ("-").

       When making programmatic	use of user properties,	it  is	strongly  sug-
       gested  to  use	a reversed DNS domain name for the module component of
       property	names to reduce	the chance  that  two  independently-developed
       packages	use the	same property name for different purposes.

       The values of user properties are arbitrary strings and are never vali-
       dated.	Use  the  zpool	set command with a blank value to clear	a user
       property.  Property values are limited to 8192 bytes.

SEE ALSO
       zpoolprops(7), zpool-set(8)

FreeBSD	14.3		       October 30, 2022			  VDEVPROPS(7)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=vdevprops&sektion=7&manpath=FreeBSD+14.3-RELEASE+and+Ports>

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