vxdmpadm(1M)															      vxdmpadm(1M)

NAME

       vxdmpadm - DMP subsystem administration

SYNOPSIS

       vxdmpadm [-a|-r|-u] cfgapm module_name
	   [attr1=value1 [attr2=value2] ...]

       vxdmpadm [-c | -f] disable
	   {ctlr=ctlr_name | enclosure=enclr_name portid=array_port_ID |
	   path=path_name | pwwn=port_WWN}
	   [enclosure=enclr_name] [type=enclr_type]

       vxdmpadm enable
	   {ctlr=ctlr_name | enclosure=enclr_name portid=array_port_ID |
	    path=path_name | pwwn=port_WWN}
	   [enclosure=enclr_name] [type=enclr_type]

       vxdmpadm getattr {enclosure enclr_name | arrayname array_name |
	   arraytype {A/A|A/P|...}} {iopolicy | partitionsize | recoveryoption}

       vxdmpadm getctlr {all | ctlr_name}

       vxdmpadm getlungroup dmpnodename=DMP_node_name

       vxdmpadm getdmpnode [enclosure=enclr_name | nodename=node_name]

       vxdmpadm getportids {ctlr=ctlr_name | dmpnodename=DMP_node_name |
	   enclosure=enclr_name | path=path_name}

       vxdmpadm getsubpaths [ctlr=ctlr_name | dmpnodename=DMP_node_name |
	   enclosure=enclr_name portid=array_port_ID |
	   pwwn=port_WWN | tpdnodename=TPD_node_name]

       vxdmpadm gettpdnode [nodename=node_name]

       vxdmpadm gettune {all | tunable}

       vxdmpadm help [attribute ...]

       vxdmpadm iostat reset

       vxdmpadm iostat show
	   {all | ctlr=ctlr_name | dmpnodename=DMP_node_name |
	   enclosure=enclr_name | pathname=path_name}
	   [interval=seconds [count=N]]

       vxdmpadm iostat start [memory=size]

       vxdmpadm iostat stop

       vxdmpadm listapm {all|module_name}

       vxdmpadm listctlr {allctlr=ctlr_name|
	   enclosure=enclr_name|type=enclr_type}

       vxdmpadm listenclosure {allenclr_name}

       vxdmpadm setattr arrayname array_name [attribute=value ...]

       vxdmpadm setattr arraytype {A/A|A/P|...}} [attribute=value ...]

       vxdmpadm setattr enclosure enclr_name [attribute=value ...]

       vxdmpadm setattr enclosure enclr_name name=new_name

       vxdmpadm setattr enclosure enclr_name tpdmode={native|pseudo}

       vxdmpadm setattr {enclosure enclr_name | arrayname array_name |
	   arraytype {A/A|A/P|...}}
	   iopolicy={adaptive | adaptiveminq | balanced [partitionsize=block_shift]|
	   minimumq | priority | round-robin | singleactive}
	   [use_all_paths={yes|no}]

       vxdmpadm setattr {enclosure enclr_name | arrayname array_name |
	   arraytype {A/A|A/P|...}}
	   recoveryoption=default

       vxdmpadm setattr {enclosure enclr_name | arrayname array_name |
	   arraytype {A/A|A/P|...}}
	   recoveryoption=fixedretry retrycount=N

       vxdmpadm setattr {enclosure enclr_name | arrayname array_name |
	   arraytype {A/A|A/P|...}}
	   recoveryoption=nothrottle

       vxdmpadm setattr {enclosure enclr_name | arrayname array_name |
	   arraytype {A/A|A/P|...}}
	   recoveryoption=throttle {iotimeout=seconds | queuedepth=N}

       vxdmpadm setattr {enclosure enclr_name | arrayname array_name |
	   arraytype {A/A|A/P|...}}
	   recoveryoption=timebound iotimeout=seconds

       vxdmpadm setattr path path_name [attribute=value ...]

       vxdmpadm setattr path path_name
	   pathtype={primary | secondary | nomanual|
	   standby | active | nopreferred | preferred [priority=N]}

       vxdmpadm settune tunable=value

       vxdmpadm start restore [attribute...]

       vxdmpadm stat errord

       vxdmpadm stat restored

       vxdmpadm stop restore

DESCRIPTION

       The  vxdmpadm  utility  is  an administrative interface to the Veritas Volume Manager (VxVM) Dynamic Multipathing (DMP) facility.  vxdmpadm
       lists the paths under a DMP device, gets the DMP device corresponding to a path, lists all the disk controllers on the  system,	lists  all
       the  paths through an HBA controller, lists all the DMP nodes through a disk array, and enables or disables I/O through a HBA controller on
       the system.

       vxdmpadm keywords select the action to perform, and attributes specify the objects on which the action is performed.

KEYWORDS

       cfgapm	 Configures the specified array policy module (APM) together with any required attribute-value pairs that specify  its	operation.
		 An  APM  is  a  dynamically loadable kernel module that is developed by array vendors for the supported array.  DMP refers to the
		 latest version of APM that is available to it.  If the current APM does not support certain arrays, DMP refers to  the  APM  with
		 the next lowest version number.

		 One of the following options may be specified for configuring the APM:

		 -a   Adds a vendor-supplied APM and configures it.

		 -r   Removes an APM if it is not busy.

		 -u   Refers DMP to the specified APM. This allows an older version of an APM to be used instead of the latest version.

       disable	 Disables  I/O	on a specified path, or on all the paths that are conected to a specified HBA controller or array port.  (An array
		 port can be specified either by the name of the enclosure and the array port ID, or by the worldwide name (WWN) identifier of the
		 array port.)  This prevents DMP from issuing I/O requests through the specified controller, path or array port.  Depending on the
		 number of pending I/O requests, this command can take some time to complete before returning control to the  user.   The  command
		 blocks until all pending I/O that was issued through the specified disk controller or path has been completed.

		 The disable operation fails with an error if it is applied to a controller that is connected to the disk through a single path.

		 The following options may be used with the disable operation:

		 -c   Checks if the specified path is the last active path to the disk.

		 -f   Forcibly disables the last active path to the disk.

		 The  disable  operation  supports  the attributes enclosure and type to specify an unambiguous path.  (A specified enclosure type
		 must be an enclosure category that supported by DMP.)

       enable	 Enables I/O on a previously disabled path, or on all the paths that are connected to a specified HBA controller  or  array  port.
		 (An array port can be specified either by the name of the enclosure and the array port ID, or by the worldwide name (WWN) identi-
		 fier of the array port.)  This operation succeeds only if the controller, path or array port is accessible to the  host  and  I/O
		 can  be  performed  on  it.  When connecting Active/Passive disk arrays, using enable results in a failback of I/O to the primary
		 path.

		 The enable operation supports the attributes enclosure and type to specify an unambiguous path.  (A specified enclosure type must
		 be an enclosure category that supported by DMP.)

       getattr	 Displays  the default and current settings of the iosize, partitionsize or recoveryoption attributes for the specified enclosure,
		 array or array type.

       getctlr	 Lists the logical and physical names of a specified controller, or of all the controllers present in the system.

       getdmpnode
		 Displays the DMP device that controls a particular physical path. The physical path is specified as the argument to the  nodename
		 attribute.  nodename must be a valid path listed in the /dev/[r]dsk directory.

		 Use the enclosure attribute with getdmpnode to obtain a list of all DMP nodes for the specified enclosure.

       getlungroup
		 Displays  all	DMP nodes in the same LUN group as the DMP node that is named as the argument to the dmpnodename attribute.  dmpn-
		 odename specifies the DMP metanode name, and must be a valid node listed in the /dev/vx/[r]dmp directory.

       getportids
		 Displays the array port ID and array port worldwide number (WWN) corresponding to the specified HBA controller, DMP node,  enclo-
		 sure or path.

       getsubpaths
		 Displays  the	paths  controlled  by  the specified HBA controller, DMP node, array port or third-party driver (TPD) device.  (An
		 array port can be specified either by the name of the enclosure and the array port ID, or by the worldwide name (WWN)	identifier
		 of the array port.)

		 A specified DMP node name must be a valid node in the /dev/vx/[r]dmp directory.

		 When  the  tpdnodename  attribute  is	used  to  specify a TPD device, the command displays the paths that DMP maintains for that
		 device, provided that the coexistence of the TPD with DMP is supported by an appropriate ASL.

		 Enabled paths which are available for I/O are indicated by ENABLED(A) in the STATE column.  A path that is enabled, but which	is
		 not  currently available for I/O, is shown as ENABLED.  For A/A arrays, all enabled paths that are available for I/O are shown as
		 ENABLED(A).  For A/P arrays in which the I/O policy is set to singleactive, only one path is  shown  as  ENABLED(A).	The  other
		 paths	are  enabled  but  not available for I/O.  If the I/O policy is not set to singleactive, DMP can use a group of paths (all
		 primary or all secondary) for I/O, which are shown as ENABLED(A).

		 A path that is set manually, rather than being discovered, is indicated by M in the PATH-TYPE column.

       gettpdnode
		 Displays the third-party driver device that corresponds to the node specified as the argument to the nodename attribute.

       gettune	 Returns the values of a specified DMP tunable parameter.  If all is specified, a list of all the DMP tunables and their values is
		 displayed.

       help	 Displays  a  detailed	information  about  attributes	used with a particular keyword. For example, to obtain a usage message for
		 listctlr, use the command:

			vxdmpadm help listctlr

       iostat	 Controls the gathering and display of I/O statistics using the following keywords:

		 reset	   Resets the counters to zero.

		 show	   Displays I/O statistics for all controllers, or for a specified controller, node, enclosure or  path.   The	statistics
			   displayed  are  the	CPU usage and amount of memory per CPU used to accumulate statistics, the number of read and write
			   operations, the number of kilobytes that are read or written, and the average time in milliseconds per kilobyte that is
			   read or written.

			   The	interval and count attributes may be used to specify the interval in seconds between displaying the I/O statistics
			   and the number of lines to be displayed. The actual interval may be smaller than the specified  value  if  insufficient
			   memory is available to record the statistics.

			   dmpnodename specifies the DMP metanode name, and must be a valid node listed in the /dev/vx/[r]dmp directory.

		 start	   Enables the gathering of I/O statistics. The memory attribute can be used to limit the maximum amount of memory that is
			   used to record I/O statistics for each CPU. The default limit is 32KB per CPU.

		 stop	   Disables the gathering of I/O statistics.

       listapm	 This displays all the APMs in the system. The list includes the file name of the module, the array type supported by the  module,
		 the APM name, APM version and status (loaded or not) of the module.

		 You can also specify a module name. The details of this module will be displayed.

       listctlr  Lists	the  HBA  controllers that are attached to the host.  listctlr all lists all controllers on the host.  You can specify the
		 enclosure, ctlr, and type attributes to display a list of controllers on a particular disk array or  on  a  particular  enclosure
		 type.

       listenclosure
		 Displays all attributes of the specified enclosure.  For example, this command displays all attributes for the disk array ENC01:
		 vxdmpadm listenclosure ENC01

		 The attribute all displays the attributes associated with all the enclosures connected to the host.

       setattr	 Assigns a new value for an attribute to the specified array, array type, enclosure or path.

		 The following attribute may be set for named arrays or enclosures, or for array types:

		 iopolicy  Determines  the I/O policy that is used to balance the I/O load across multiple paths to a disk array or enclosure in a
			   system.  You can set policies for an enclosure (for example, HDS01), for all enclosures of a particular type (for exam-
			   ple, HDS), or for all enclosures of a particular array type (for example, A/A for active/active and A/P for active/pas-
			   sive).

			   The policies that can be set are:

			   adaptive  In SAN environments, determines the paths that have the least delay, and schedules  I/O  on  paths  that  are
				     expected to carry a higher load.  Priorities are assigned to the paths in proportion to the delay.

			   adaptiveminq
				     Similar to the adaptive policy, except that I/O is scheduled according to the length of the I/O queue on each
				     path. The path with the shortest queue is assigned the highest priority.

			   balanced [partitionsize=block_shift]
				     Takes the track cache into consideration when balancing I/O across paths.

				     The size of the track cache may be specified using the partitionsize attribute. The size  is  in  blocks  and
				     should  be  a power of 2.	If the specified size is not a power of 2, it is rounded down to the nearest power
				     of 2.  A block_shift of 0 selects the default value of 1024 blocks(1MB).

			   minimumq  Uses a minimum I/O queue policy. I/O is sent on paths that have the minimum number of  I/O  requests  in  the
				     queue.  This policy is suitable for low-end disks or JBODs where a significant track cache does not exist.

				     This is the default policy for Active/Active (A/A) arrays.

			   priority  Assigns the path with the highest load carrying capacity as the priority path.  (The path priority may be set
				     using the vxdmpadm setattr path command.)	This policy is useful when the paths in a SAN have unequal perfor-
				     mance, and you want to enforce load balancing manually.

			   round-robin
				     Sets a simple round-robin policy for I/O.

				     This is the default policy for Active/Passive (A/P) and Asynchronous Active/Active (A/A-A) arrays.

			   singleactive
				     I/O is channeled through the single active path.

			   The	optional attribute use_all_paths controls whether the secondary paths in an Asymmetric Active/Active (A/A-A) array
			   are used for scheduling I/O requests in addition to the primary paths.  The default setting is no, which disallows  the
			   use of the secondary paths.

		 recoveryoption
			   Specifies  how  DMP responds to failed I/O requests on a path.  You can set recovery options for the paths to an enclo-
			   sure (for example, HDS01), for the paths to all enclosures of a particular type (for example, HDS), or for the paths to
			   all enclosures of a particular array type (for example, A/A for active/active and A/P for active/passive).

			   The recovery options that can be set are:

			   default   Corresponds to setting both fixedretry retrycount=5 and throttle iotimeout=10 on the paths.

			   fixedretry
				     DMP retries failed I/O requests on a path for the number of times specified by retrycount.  The default value
				     for retrycount is 5.

			   nothrottle
				     Turns off I/O throttling for a path.

			   throttle  Enables I/O throttling for a path.

				     If a timeout in seconds is specified using iotimeout, DMP continues to schedule I/O requests  on  a  path	on
				     which  an I/O failure has occurred for that many seconds.	It will then prevent new I/O requests being sched-
				     uled on the path, and attempt to reschedule failed I/O requests  on  other  paths.   The  default	value  for
				     iotimeout is 10 seconds.

				     If  a  maximum  number  of  queued  I/O requests is specified using queuedepth, DMP continues to schedule I/O
				     requests on a path on which an I/O failure has occurred until the queue limit is reached.	It will then  pre-
				     vent  new	I/O  requests  being scheduled on the path, and attempt to reschedule failed I/O requests on other
				     paths.  The default value for queuedepth is 20.

				     Only one of iotimeout or queuedepth may be specified.

			   timebound DMP retries failed I/O requests on a path for the time in seconds specified by iotimeout.	The default  value
				     for iotimeout is 10 seconds.

			   The nothrottle and throttle options, and the fixedretry and timebound options are mutually exclusive for a given path.

			   The settings of iotimeout for throttle and for timebound are independent of each other.

		 The following attributes may be set for enclosures:

		 name	   Assigns a new name to the specified enclosure.  Each enclosure must have a unique name.  This name can be used to refer
			   to the enclosure during any vxdmpadm operation.

			   The new name cannot be more than 25 characters.  If a name exceeds this length, setattr fails with an error message.

		 tpdmode   Specifies the form of device names that VxVM commands such as vxdisk display for devices that are controlled by  third-
			   party  drivers  (TPDs)  whose  coexistence is supported by an appropriate ASL. If set to pseudo (default), the TPD node
			   name is used.  If set to native, the subpath with the smallest device number known to the operating system is used.

			   Note: This feature can only be used if the default naming scheme is set to use operating system-based naming,  and  the
			   TPD-controlled enclosure does not contain fabric disks.

		 The following attributes may be set for paths:

		 active    Changes a standby path to active.

		 nomanual  Restores the original primary or secondary attributes of a path.

		 nopreferred
			   Restores the normal priority of the path.

		 preferred [priority=N]
			   Specifies a preferred path, and optionally assigns a priority value to it.  This indicates a path that is able to carry
			   a higher I/O load.  The priority value must be an integer greater than or equal to 1.  Larger priority values  indicate
			   a greater load carrying capacity.

			   Note: Marking a path as a preferred path does not change its I/O load balancing policy.

		 primary   Assigns a primary path for an Active/Passive disk array.

		 secondary Assigns a secondary path for an Active/Passive disk array.

		 standby   Marks a path as not available for normal I/O scheduling.  This path is only invoked if there are no active paths avail-
			   able for I/O.

       settune	 Sets the value of the specified DMP tunable parameter.  This value takes precedence over any value that is set using  the  method
		 provided by the operating system. The changed value is persistent across reboots of the system.

		 The following tunable parameters may be changed for DMP:

		 dmp_cache_open
			   If  set to on, the first open on a device that is performed by an array support library (ASL) is cached.  This enhances
			   the performance of device discovery by minimizing the overhead caused by subsequent opens by  ASLs.	 If  set  to  off,
			   caching is not performed.  The default setting is off.

		 dmp_daemon_count
			   The	number	of  kernel  threads  that  are available for servicing path error handling, path restoration and other DMP
			   administrative tasks.  The default number of threads is 10.

		 dmp_delayq_interval
			   How long DMP should wait before retrying I/O after an array fails over to a standby path.  Some disk arrays are not	be
			   capable of accepting I/O requests immediately after failover.  The default value is 15 seconds.

		 dmp_failed_io_threshold
			   The	time limit that DMP waits for a failed I/O request to return before the device is marked as INSANE, I/O is avoided
			   on the path, and any remaining failed I/O requests are returned to the application layer without performing	any  error
			   analysis.  The default value is 57600 seconds.

		 dmp_fast_recovery
			   Whether  DMP  should attempt to obtain SCSI error information directly from the HBA interface.  Setting the value to on
			   can potentially provide faster error recovery, provided that the HBA interface supports the error enquiry feature.	If
			   set to off, the HBA interface is not used.  The default setting is off.

		 dmp_health_time
			   The time in seconds for which a path must stay healthy.  If a path's state changes back from enabled to disabled within
			   this time period, DMP marks the path as intermittently  failing,  and  does	not  re-enable	the  path  for	I/O  until
			   dmp_path_age  seconds  elapse.   The  default  value  of dmp_health_time is 60 seconds.  A value of 0 prevents DMP from
			   detecting intermittently failing paths.

		 dmp_log_level
			   The level of detail that is displayed for DMP console messages.  The following level values are defined:

			   1	Display all DMP log messages that existed in releases before 5.0.  This is the default setting.

			   2	Display level 1 messages plus messages that relate to I/O throttling, suspected paths, repeated path failures  and
				DMP node migration.

			   3	Display level 1 and 2 messages plus messages that relate to I/O errors, I/O error analysis and path media errors.

			   4	Display level 1, 2 and 3 messages plus messages that relate to setting or changing attributes on a path.

		 dmp_path_age
			   The	time  for  which an intermittently failing path needs to be monitored as healthy before DMP once again attempts to
			   schedule I/O requests on it.  The default value is 300 seconds.  A value of 0 prevents  DMP	from  detecting  intermit-
			   tently failing paths.

		 dmp_pathswitch_blks_shift
			   The	default  number of contiguous I/O blocks (expressed as the integer exponent of a power of 2; for example 11 repre-
			   sents 2048 blocks) that are sent along a DMP path to an Active/Active array before  switching  to  the  next  available
			   path.  The default value of this parameter is set to 10 so that 1024 blocks(1MB) of contiguous I/O are sent over a DMP
			   path before switching.  This value may be overridden for individual paths by specifying a partitionsize  value  to  the
			   setattr iopolicy=balanced operation.

		 dmp_probe_idle_lun
			   If DMP statistics gathering is enabled, set to on (default) to have the path restoration kernel thread probe idle LUNs,
			   or to off to turn off this feature.	(Idle LUNs are VM disks on which no I/O requests are  scheduled.)   The  value	of
			   this  tunable is only interpreted when DMP statistics gathering is enabled.	Turning off statistics gathering also dis-
			   ables idle LUN probing.

		 dmp_queue_depth
			   The maximum number of queued I/O requests on a path during I/O throttling.  The default value is 40.  This value may be
			   overridden for individual paths by specifying a queuedepth value to the setattr recoveryoption=throttle operation.

		 dmp_retry_count
			   The	number of retries to attempt on a path if there is an I/O error.  The default number of retries is 30.	This value
			   may be overridden for individual paths by specifying a fixedretry value to the setattr recoveryoption=fixedretry opera-
			   tion.

		 dmp_retry_timeout
			   The	maximum  time  period  for which DMP retries the SCSI-3 Persistent Reserve operation with A/P arrays.  The default
			   value is 0 seconds, which disables this feature.  This parameter has no direct effect on I/O processing by DMP.

			   Disabling a switch port can trigger a fabric reconfiguration, which can take time to stabilize.   During  this  period,
			   attempting  to  register PGR keys through the secondary path to an array may fail with an error condition, such as unit
			   attention or device reset, or the return of vendor-specific sense data.  The retry period allows a fabric  reconfigura-
			   tion (usually a transient condition) to not be seen as an error by DMP.

			   Note:  Do not set the value of the retry period too high.  This can delay the failover process, and result in I/O slug-
			   gishness or suppression of I/O activity during the retry period.

		 dmp_scsi_timeout
			   Determines the timeout value to be set for any SCSI command that is sent via DMP.   If  the	HBA  does  not	receive  a
			   response for a SCSI command that it has sent to the device within the timeout period, the SCSI command is returned with
			   a failure error code.

			   The default value is 60 seconds.

		 dmp_stat_interval
			   The time interval between gathering DMP statistics.	The default and minimum value is 1 second.

       start restore
		 Starts the kernel thread that implements DMP path restoration.  This thread analyzes the condition of paths every  interval  sec-
		 onds. The type of analysis depends on the specified policy:

		 check_all The path restoration thread analyzes all paths in the system and revives the paths that are back online as well as dis-
			   ables the paths that are inaccessible.

		 check_alternate
			   The path restoration thread checks that at least one alternate path is healthy. It  generates  a  notification  on  the
			   first occasion that this condition is not met.

			   If there are less than two active (and enabled) paths under a DMP node, vxnotify displays the message "dmpnode name has
			   N alternate paths."

			   Note: This policy avoids inquiry commands on all healthy paths, and is less costly than  check_all  in  cases  where  a
			   large number of paths are available.  This policy reduces to check_all if there are only two paths per DMP node.

		 check_disabled
			   The	path  restoration  thread checks the condition of paths that were previously disabled due to hardware failures and
			   revives them if they are back online.

		 check_periodic
			   The path restoration thread performs check_all once in a given number of cycles, and check_disabled in the remainder of
			   the cycles.

			   Note: This policy may lead to periodic slowing down (due to check_all) if there are large number of paths available.

		 The default policy is check_disabled.	To change the interval or policy, you must stop the path restoration thread and restart it
		 with new attributes.

		 To set the policy to check_all, enter:

			vxdmpadm start restore policy=check_all

		 If a controller disabled using the following command, the path restoration thread does not change the disabled state of the  path
		 through it.

			vxdmpadm disable ctlr=ctlr

		 To set the polling interval to 400 seconds, enter:

			vxdmpadm start restore interval=400

		 Caution: The default polling interval is 300 seconds.	Decreasing this interval can adversely affect system performance.

		 The check_periodic policy can be invoked as follows:

			vxdmpadm start restore policy=check_periodic 
			    interval=t [period=n]

		 Note: A polling interval must be specified. This specifies how often (in seconds) the DMP path restoration thread checks the sta-
		 tus of disabled paths.

		 The period n is the number of times that check_disabled is invoked before check_all is invoked. This sequence is then repeated.

		 The integer value n of period can either be specified on the command line, or set as a  tunable  dmp_restore_daemon_cycles  (this
		 requires  a  system shutdown and reboot to take effect).  The value of period specified on the command line takes precedence.	If
		 not specified in either of these ways, the default period is 10.

		 The check_alternate policy can be invoked as follows:

			vxdmpadm start restore policy=check_alternate 
			    interval=t

       stat errord
		 Displays the number of error handling threads that are running.

       stat restored
		 Displays the status of the automatic path restoration daemon, the interval of polling, and the policy used to check the condition
		 of paths.

       stop restore
		 Stops the DMP path restoration thread.  Automatic path failback stops if the path restoration thread stops.

EXIT CODES

       vxdmpadm  exits	with  a  zero status if the attempted operation succeeds. A non-zero exit code is not a complete indicator of the problems
       encountered, but rather denotes the first condition that prevented further execution of the utility.

       See vxintro(1M) for a list of standard exit codes.

EXAMPLES

       To display the usage message for all vxdmpadm commands, enter:

	    vxdmpadm help

       To list all attributes of all HBA controllers on the system, enter:

	    vxdmpadm listctlr all

       To list all attributes of all the enclosures on the system, enter:

	    vxdmpadm listenclosure all

       To list all attributes of the disk array enc0, enter:

	    vxdmpadm listenclosure enc0

       Assign the new name l1e1 to the disk array ENC01:
	    vxdmpadm setattr enclosure ENC01 name=l1e1

       To disable I/O through the HBA controller c2, enter:

	    vxdmpadm disable ctlr=c2

       If you then run the listctlr all command, the state of the controller c2 is shown as disabled.  To enable the HBA controller c2, which  was
       disabled by vxdmpadm disable ctlr=c2, enter:

	    vxdmpadm enable ctlr=c2

       Executing  listctlr  all after this command shows the state of the controller c2 as enabled.  The following examples outline the attributes
       supported by vxdmpadm listctlr.

	    vxdmpadm listctlr all
	    vxdmpadm listctlr enclosure=enc0 type=ENC
	    vxdmpadm listctlr type=ENC
	    vxdmpadm listctlr enclosure=enc0
	    vxdmpadm listctlr ctlr=c2

       The following command lists all paths controlled by the DMP node c2t1d0s2.

	    vxdmpadm getsubpaths dmpnodename=c2t1d0s2

       The following command obtains all paths through the HBA controller c2.

	    vxdmpadm getsubpaths ctlr=c2

       The following command displays the DMP node that controls the node c3t2d1s2.

	    vxdmpadm getdmpnode nodename=c3t2d1s2

       The following command displays the DMP nodes connected to the enclosure enc0.

	    vxdmpadm getdmpnode enclosure=enc0

       The following command assigns a new name, VMGRP_1, to the enclosure enc0.

	    vxdmpadm setattr enclosure enc0 name=VMGRP_1

       To start the path restoration thread with the default interval (300 seconds) and default policy (check_disabled), enter:

	    vxdmpadm start restore

       To specify the interval of polling as 400 seconds, enter:

	    vxdmpadm start restore interval=400
       The daemon checks the condition of the paths as specified by the policy attribute. To set the policy as check_all, enter:
	    vxdmpadm start restore policy=check_all

       The following command stops the DMP path restoration thread; the thread is automatically  started  at  system  startup  time  with  default
       attributes.
	    vxdmpadm stop restore

       To list the intervals of the path restoration thread and the number of error handling threads, enter:

	    vxdmpadm stat restored
	    vxdmpadm stat errord

       Set the I/O policy to round-robin for the enclosure SENA0, and to balanced for arrays of type SENA:
	    vxdmpadm setattr enclosure SENA0 iopolicy=round-robin
	    vxdmpadm setattr arrayname SENA iopolicy=balanced partitionsize=2048

       Set c1t10d0 as a standby path:
	      vxdmpadm setattr path c1t10d0 pathtype=standby

       Set c1t20d0 as an active path:
	      vxdmpadm setattr path c1t20d0 pathtype=active

       Set c2t20d0 as a preferred path with priority 2:
	      vxdmpadm setattr path c2t20d0 pathtype=preferred priority=2

       Reset the priority on path c2t20d0:
	      vxdmpadm setattr path c2t20d0 pathtype=nopreferred

       Display operating system device names instead of TPD node names for the enclosure EMC0:

	    vxdmpadm setattr enclosure EMC0 tpdmode=native

       Enable I/O throttling with a timeout of 400 seconds for all paths to the enclosure enc1:

	    vxdmpadm setattr enclosure enc1 recoveryoption=throttle iotimeout=400

       Turn off I/O throttling for all paths to the enclosure enc1:

	    vxdmpadm setattr enclosure enc1 recoveryoption=nothrottle

       Enable time-bound I/O recovery with a timeout of 600 seconds for all paths to the enclosure enc1:

	    vxdmpadm setattr enclosure enc1 recoveryoption=timebound iotimeout=600

       Display details of the array ports that are configured for the enclosure enc2:

	    vxdmpadm getportids enclosure=enc2

NOTES

       The terms disk array and enclosure are synonymous.

       If only a Base VxVM license is installed, the vxdctl license command displays "DMP (single path enabled)".  If either the Full VxVM license
       or an automatically generated license (such as that for the PHOTON array) is installed, the command displays "DMP (multipath enabled)".

FILES

       /etc/vx/dmppolicy.info
		       Persistent file used to store DMP policy settings.

SEE ALSO

       vxdctl(1M), vxintro(1M)

VxVM 5.0.31.1							    24 Mar 2008 						      vxdmpadm(1M)