System Administration Commands iiadm(1M)
NAME
iiadm - command-line interface to control Sun StorageTek
Availability Suite Point-in-Time Copy operations
SYNOPSIS
iiadm -e {ind | shd} master_vol shadow_vol bitmap_vol
iiadm -ne ind master_vol shadow_vol bitmap_vol
iiadm [-p] [-n] {-c | -u} {s | m} volume_set
iiadm [-adDilR] volume_set
iiadm [-p] [-n] -w volume_set
iiadm [-hilLv]
iiadm -P delay units volume_set
iiadm -P volume_set
iiadm -A overflow_vol volume_set
iiadm [-OQ] overflow_vol
iiadm -E volume_set
iiadm [-IJ] volume_set bitmap
iiadm -g group_name [-aAcdDeEilLmPRuw]
iiadm [-C] cluster_tag [options]
DESCRIPTION
Point-in-Time Copy software is a point-in-time snapshot
feature of the Solaris operating system.SunOS 5.11 Last change: 2 Oct 2007 1
System Administration Commands iiadm(1M)
A Point-in-Time Copy snapshot is an instantly-available,
time-fixed, replicated view of a momentarily quiesced
volume. Once a snapshot is taken, Point-in-Time Copy
software allows immediate read/write access to both the mas-
ter and shadow volume data.Point-in-Time Copy software tracks the differences between
the master and shadow volumes (caused by writes) from the moment that the snapshot was established. This capability allows applications accessing the master volume's data to move forward in time independently of applications accessingthe shadow volume's data, and vice-versa.
The Point-in-Time Copy software's tracking of differences
between the master and shadow volumes facilitates a fast resynchronization or a full copy at a later time. The volume resynchronization can occur from either shadow to master or master to shadow.Instantly after the point-in-time is (re-)established
(either when the CLI prompt returns or the next shell script command is read), the master volume can be remounted or the applications using them can be resumed. Also, the shadow volume can be mounted and immediately accessed.The iiadm command line utility performs only one action per
command invocation. Because of this, you cannot combine mul-
tiple options, except in combination with the following overall command modifiers:o If no action item is entered, iiadm displays the
list of Point-in-Time Copy sets (non-suspended)
currently configured. If more than one action item, or an incorrectly specified action item is entered,iiadm displays the specific error message to
stderr, followed by a brief usage summary.o For the Point-in-Time Copy options ENABLE (-e),
COPY (-c) and UPDATE (-u), there are two associated
shadow volume selection qualifiers, {ind|dep}, thatare used to specify the type of Point-in-Time Copy
volume set to create.An independent (ind) snapshot causes Point-in-Time Copy
software to perform a full volume copy operation from the master to the shadow. When the copy completes, the shadow volume data is identical to the master volume data at theSunOS 5.11 Last change: 2 Oct 2007 2
System Administration Commands iiadm(1M)
moment that it was established. Create an independent shadowif you require two physical copies of the data. An indepen-
dent shadow volume must be the same size or greater than the size of the master volume. Sun recommends that the master and shadow volumes be the same size for environments where resynchronization from shadow to master is a consideration.A dependent (dep) snapshot causes Point-in-Time Copy
software not to perform a full volume copy. The resulting shadow volume relies on the master volume for all unmodified data blocks, which are not copied until requested. Create a dependent shadow when you do not require two physical copies of the data. A dependent shadow volume can be either thesame size or smaller than the master volume. A smaller sha-
dow volume is called a Compact Dependent Shadow Volume, and is typically used when the amount of change that occurs to aPoint-in-Time Copy volume set is small compared to the
entire size of the master volume. The following syntax allows you to create an exportable independent shadow volume in a Sun Cluster environment:# iiadm -ne ind master shadow bitmap
An issue arises when using a Compact Dependent Shadow Volumein that its size is established at the time that the Point-
in-Time Copy volume set is enabled. If the amount of change
to the entire volume set over the duration of its usageexceeds the space allocated for the shadow volume, the sha-
dow volume is marked as out of space. It is possible to read from the shadow volume even after it is out of space, until a portion of the data for which there was no room is requested. Once that happens, the read fails and the shadow volume is marked offline.To address this issue, Point-in-Time Copy supports the abil-
ity to associate an overflow volume to an existing Point-
in-Time Copy dependent volume set. Thus, if the size of the
Compact Dependent Shadow Volume is too small, or an unscheduled amount of change occurs to the volume set, changed data can be redirected to the associated overflow volume. To facilitate efficient usage of this overflowvolume, it can be associated with multiple Point-in-Time
Copy volume sets on an as-needed basis.
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System Administration Commands iiadm(1M)
ConsiderationsPrior to invoking an Point-in-Time Copy enable, copy or
update operation, Point-in-Time Copy assures that the shadow
volume is not mounted, to prevent a file system panic from occurring. Also, it is suggested that you either unmount or suspend (quiesce) all applications using the master volume,for only the instant when the point-in-time snapshot is
taken. This assures that an atomically consistent point-in-
time snapshot is taken. It is suggested that, if the master volume was suspendedrather than unmounted, the new point-in-time shadow volume's
integrity be validated using volume validation utilities,such as fsck(1M). The reason is that Point-in-Time Copy has
made a point-in-time copy of a mounted master volume to an
unmounted shadow volume. During the mounting of the shadow volume, the file system detects that it is in the mounted state. Typically this state occurs only when a system crashes, so the file system attempts to validate the integrity of the volume assuming a system failure occurred,not an Point-in-Time Copy.
ENVIRONMENT OPTIONSThe ii_bitmap variable in the /usr/kernel/drv/ii.conf confi-
guration file determines the bitmap volume operational semantics as follows: 0 Indicates that the bitmap is maintained in memory only or resume operation. 1 Indicates that the bitmap is maintained in memory and on disk. This is the default value.If a system failure occurrs while using ii_bitmap=0, the
shadow volume might be inconsistent and fast resynchroniza-
tion would not be possible.If Point-in-Time Copy is used in conjunction with the Net-
work Storage component Remote Mirror or in a Sun Cluster,set ii_bitmap=1.
The ii_debug variable in the /usr/kernel/drv/ii.conf confi-
guration file determines the amount of information logging that is output to the system console /dev/console duringPoint-in-Time Copy processing.
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System Administration Commands iiadm(1M)
0 Indicates that no logging is sent to the system console. 1 Indicates that informational logging is sent to the system console. 2 Indicates that developmental logging is sent to the system console. OPTIONSThe iiadm utility supports the following options.
-e{ind|dep} master_vol shadow_vol bitmap_vol
Enable Point-in-Time Copy for the specified master, sha-
dow, and bitmap volumes.The enable shadow set processing assures that the speci-
fied volumes are accessible, that the shadow_vol is not
mounted, and that the bitmap_vol is correctly sized for
the type of shadow set being created. Additionally, it assures that the volumes are under control of the SVdriver ( if they are not, it puts them there), initial-
izes the bitmap volume, and, if the volume set is anindependent shadow set, a full copy operation is ini-
tiated.On a successful enable, Point-in-Time Copy stores the
specified master_vol, shadow_vol and bitmap_vol names,
plus the enabling type (ind or dep), into the Point-in-
Time Copy configuration store. The configuration storecontains all currently configured Point-in-Time Copy
Volume Sets and their associated configuration attri-
butes. (See discussion above on independent and depen-
dent shadow volume semantics.)master_vol is the volume from which a point-in-time
snapshot is made.shadow_vol is the volume that contains the point-in-time
snapshot.bitmap_vol is used for tracking differences between the
shadow and master volumes. When Point-in-Time Copy sha-
dow operations are suspended or resumed, the bitmap volume (maintained in kernel memory) can be stored in or retrieved from permanent storage. The storage associated with the bitmap volume should be as redundant as that of the shadow volume storage.SunOS 5.11 Last change: 2 Oct 2007 5
System Administration Commands iiadm(1M)
The shadow_vol name is the name that the Point-in-Time
Copy Shadow Set is known by for all iiadm options
requiring specification of a volume_set name.
-d volume_set
Disable the Point-in-Time Copy volume set associated
with the specified volume_set.
If Point-in-Time Copy was running in independent mode as
specified in the -e ind options, above, the shadow
volume data contains the same data as it did before it was disabled (assuming no writes have occurred). Users can access the master and shadow volumes, as they arenow standalone point-in-time copies.
During the time that the full copy is active, an independent volume operates as though it is a dependent volume. To assure that the volume is no longer in full copy mode, issue the following command to wait for the full copy to complete:# iiadm -w volume_set
[-p] -u s volume_set
Update the shadow volume from the master.Updates a point-in-time copy of the master volume to the
shadow volume. volume_set is the Point-in-Time Copy sha-
dow set containing the master and shadow volumes. This option provides a fast resynchronization of the shadow volume, creating an incremental copy of the master. This update copies all 32KB segments flagged as different between the master and shadow volumes. It does not copy all master volume data, only changed data. While the data is being copied, the shadow is dependent upon the master volume.Before using this option, momentarily quiesce the work-
load to the volumes; stop the host application fromwriting to the volumes. This ensures that the point-in-
time data is consistent. You can visually check thestatus of this copy or update operation with iiadm -i
volume_set, or interactively (by means of a shell or
script) with iiadm -w volume_set, before using the tar-
get volume for any other operations.SunOS 5.11 Last change: 2 Oct 2007 6
System Administration Commands iiadm(1M)
This command supports PID (Process IDentifier) locking,by using the option -p, iiadm -p -u s. Enabling this
option prevents other processes from taking a newpoint-in-time snapshot, thus invalidating prior point-
in-time data.
[-p] [-n] -u m volume_set
Updates a point-in-time copy of the master volume from
the shadow. volume_set is the Point-in-Time Copy volume
set containing the master and shadow. This option pro-
vides a fast resynchronization of the master volume, creating an incremental copy of the shadow. This update copies all 32KB segments flagged as different betweenthe master and shadow volumes. It does not copy all sha-
dow volume data, only changed data. While the data is being copied, the master is dependent upon the shadow volume.Before using this option, momentarily quiesce the work-
load to the volumes; stop the host application fromwriting to the volumes. This ensures that the point-in-
time data is consistent. You can visually check thestatus of this copy or update operation with iiadm -i
volume_set, or interactively (by means of a shell or
script) with iiadm -w volume_set, before using the tar-
get volume for any other operations. This command is query enabled to prevent accidentallyoverwriting the data on a master volume. When this com-
mand option is used in scripts, add the -n option to
prevent the query from occurring. This command supports PID (Process IDentifier) locking,by using the option -p, iiadm -p -u m. Enabling this
option prevents other processes from taking a newpoint-in-time snapshot, thus invalidating prior point-
in-time data.
[-p] -c s volume_set
Copy the master volume to the shadow.Creates a point-in-time copy of the master volume to the
shadow volume. volume_set is the Point-in-Time Copy
volume set containing the master and shadow. This optionwrites all data in the point-in-time copy of the master
volume to the shadow volume. While the data is being copied from master to shadow, the shadow is dependent on the master volume.SunOS 5.11 Last change: 2 Oct 2007 7
System Administration Commands iiadm(1M)
This option performs a full volume copy. Use iiadm -u s
unless the integrity of the data on the independent sha-
dow volume is in doubt. Otherwise, use this option to synchronize the master and shadow volumes; that is, make the data on each volume match.Before using this option, momentarily quiesce the work-
load to the volumes; stop the host application fromwriting to the volumes. This ensures that the point-in-
time data is consistent. You can visually check thestatus of this copy or update operation with iiadm -i
volume_set, or interactively (by means of a shell or
script) with iiadm -w volume_set, before using the tar-
get volume for any other operations. This command supports PID (Process IDentifier) locking,by using the -p option, iiadm -p -c s. Enabling this
option prevents other processes from taking a newpoint-in-time snapshot, thus invalidating prior point-
in-time data.
-c m volume_set
Copy the shadow volume to the master.Creates a point-in-time copy of the shadow volume to the
master volume. volume_set is the Point-in-Time Copy
volume set containing the master and shadow volumes.This option writes all data in the point-in-time copy of
the shadow volume to the master volume. While the datais being copied from the shadow to the master, the mas-
ter is dependent upon the shadow volume.This option performs a full volume copy. Use iiadm -u m
unless the integrity of the data on the independent mas-
ter is in doubt. Otherwise, use this option to synchron-
ize the master and shadow volumes; that is, make the data on each volume match.Before using this option, momentarily quiesce the work-
load to the volumes; stop the host application fromwriting to the volumes. This ensures that the point-in-
time data is consistent. You can visually check thestatus of this copy or update operation with iiadm -i
volume_set, or interactively (by means of a shell or
script) with iiadm -w volume_set, before using the tar-
get volume for any other operations.This command is query-enabled to prevent accidentally
overwriting the data on a master volume. When this com-
mand option is used in scripts, add the -n option to
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System Administration Commands iiadm(1M)
prevent the query from occurring. This command supports PID (Process IDentifier) locking,by using the -p option, iiadm -p -c m. Enabling this
option prevents other processes from taking a newpoint-in-time snapshot, thus invalidating prior point-
in-time data.
-a volume_set
Abort any current copy operation that might be activebetween the master and shadow volumes. volume_set is the
Point-in-Time Copy volume set containing the master and
shadow volumes. After executing iiadm -a, the update or
copy to the target (master or shadow) volume is incom-
plete. The target volume is now a dependent copy of the source volume. Reissue the update or copy command option to resynchronize the volumes.[-p] [-n] -w volume_set
Wait until any in-progress copy or update operation com-
pletes or is aborted. volume_set is the Point-in-Time
Copy volume set containing the master and shadow volumes.This option waits until the current Point-in-Time Copy
operation is complete, thus preventing a subsequentiiadm command (from a shell or script) from executing.
Use this command option when you need to be sure the copy or update operation has completed.This command supports PID (Process IDentifier) unlock-
ing. If a prior copy or update, using a command iiadm -p
{-c|-u} {m|s}, was invoked with the -p option, upon com-
pletion of the wait processing, if the current PID wasthe PID that locked the point-in-time data, this option
unlocks the data.-i volume_set
Display status for the Point-in-Time Copy currently-
enabled or -suspended volume set. volume_set is the
Point-in-Time Copy volume set containing the master and
shadow volumes. If no volume_set is specified, status is
displayed for all Point-in-Time Copy volume sets that
are configured.SunOS 5.11 Last change: 2 Oct 2007 9
System Administration Commands iiadm(1M)
-l
List all currently configured Point-in-Time Copy
volumes.-O overflow_vol
This option causes Point-in-Time Copy to initialize the
specified overflow_vol for subsequent use as an overflow
volume in conjunction with Compact Dependent Shadow Volumes. To facilitate efficient, shared usage of this overflow volume, it can be associated with multiplePoint-in-Time Copy volume sets on an as-needed basis.
During initialization of the overflow_vol, the initiator
of this option, must answer the following question: "Initialize this overflow volume? yes/no" A response of either "yes/no" is required before proceeding.This option supports the -n option, so that the
requested action is performed without prompting. Thisoption is useful for inclusion in a script. The -n
option must be specified first. For example, "iiadm -nO
vol" is valid; "iiadm -On vol" is not.
Make sure you want to initialize the data on the speci-
fied overflow_vol, especially when using the -n option.
-A overflow_vol volume_set
This option enables the specified overflow_vol, for sub-
sequent use as an overflow volume in a situation where the size of the Compact Dependent Shadow Volume is too small, or an unscheduled amount of change occurs to the volume set. Overflow changed data would be redirected tothe associated overflow volume. volume_set is the
Point-in-Time Copy volume set containing the master and
shadow volumes.If the overflow_vol has not been initialized, this
option initializes the overflow_vol (see -O option),
then attaches the overflow_vol to the volume_set.
If overflow_vol was previously initialized, this option
attaches the overflow_vol to the volume_set.
This option supports the -n option, so that the
requested action is performed without prompting. Thisoption is useful for inclusion in a script. The -n
option must be specified first. For example, "iiadm -nA
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System Administration Commands iiadm(1M)
vol" is valid; "iiadm -An vol" is not.
Make sure you want to initialize the data on the speci-
fied overflow_vol, especially when using the -n option.
-D volume_set
This option removes the overflow volume currently asso-
ciated with the specified volume_set. If the overflow
volume is currently in use by the volume_set, this
operation fails with an "Overflow volume still in use" error message. To resolve this situation, perform one ofthe operations described below on the volume_set. These
operations momentarily clear out all overflow writes that are associated with this volume set.abort(-a)
Abort copy operation.disable(-d)
Dissolve the volume set.update(-u)
Update the volume set.-L
This option lists all overflow volumes which are associ-
ated with one or more volume sets.-Q overflow_vol
This option displays the current status of theoverflow_vol.
-E volume_set
Export the independent shadow volume of the Point-in-
Time Copy volume set specified by volume_set. The shadow
volume is to be made available to another host for read/write access, by means of an enabling technology,such as multi-ported devices. This other host is
SunOS 5.11 Last change: 2 Oct 2007 11
System Administration Commands iiadm(1M)
responsible for maintaining a bitmap of differences that is used to merge with locally recorded differences to the master when the shadow volume is rejoined to its master volume. While a shadow volume is exported it must not be subject to an update or copy operation. Performan iiadm -w volume_set command prior to invoking an
export command.-I volume_set bitmap_vol
Import the independent shadow volume of the Point-in-
Time Copy volume set specified by volume_set. The shadow
volume must have been previously exported from a host bymeans of an enabling technology, such as multi-ported
devices. The import operation causes this host to start maintaining a bitmap of differences as the volume ismodified. The bitmap_vol should not be the same as that
used when the shadow volume was originally formed into a shadow group. After the exported/imported independent shadow volume is no longer needed by the other node, you must enter adisable command so that the bitmap_vol and its associ-
ated shadow_vol are consistent, prior to performing a
join operation. For example,# iiadm -d volume_set
-J volume_set bitmap_vol
Join the volume_set, using the bitmap_vol, with the mas-
ter volume set of the Point-in-Time Copy volume set. The
bitmap volume supplied is read and merged with the ori-
ginal volume to reconstruct the original volume set con-
sisting of the master, shadow, and bitmap volumes. Thebitmap_vol to be merged is the one obtained on the node
that had imported the independent shadow volume. There must be no write activity to the shadow volume on the importing machine from the time the bitmap is copied over until the shadow is once again imported.-g group_name -m volume_set [volume_set2 ...]
Add one or more existing Point-in-Time Copy
volume_set(s) into a user specified group_name. This
association of one or more Point-in-Time Copy volume
sets in a group allows the list of iiadm options shown
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System Administration Commands iiadm(1M)
below to be performed on all volume sets within thegroup_name as a whole.
Only the commands COPY (-c) and UPDATE (-u) are per-
formed atomically across all Point-in-Time Copy sets
within the group. All other grouped, iiadm commands are
performed sequentially on each member of the group.The syntax of an iiadm group command is as follows:
iiadm -g group_name [options]
The options are as follows:-a
Abort copy operation on all sets within group_name.
-A
Attach overflow_vol to all sets within group_name.
-c {s | m}
Copy shadow/master for all sets within group_name.
-D
Detach overflow_vol from all sets within group_name.
-d
Disable all sets within group_name.
-E
Export all volume sets within group_name.
-i
Status of all volume sets within group_name.
-l
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System Administration Commands iiadm(1M)
List all volume sets within group_name.
-L
List all groups.-n
Do not ask if an update of the master volume is what the user really intended.-P
Set parameters on all volume sets within group_name.
-R
Reset all volume sets within group_name.
-u {s | m}
Update shadow/master for all sets within group_name.
-w
Wait for all volume sets within group_name.
-g -" " -m volume_set [volume_set2 ...]
Remove one or more existing Point-in-Time Copy
volume_set(s) from their currently associated
group_name. By default, or until moved into a user
specified group_name, all Point-in-Time Copy
volume_set(s) are in the blank (" ") group. This associ-
ation allows all the previously documented iiadm group
commands to be performed against the blank (" ") iiadm
group_name.
-C cluster_tag
This Point-in-Time Copy option is a modifier that limits
configuration operations to only those volumes belonging to a Sun Cluster Resource Group, or Disk Group.SunOS 5.11 Last change: 2 Oct 2007 14
System Administration Commands iiadm(1M)
In a Sun Cluster where the volume manager is SunCluster-aware, iiadm automatically obtains the correct
Disk Group information, therefore this option is typi-
cally not required unless the volumes are part of an encompassing Resource Group. In a Sun Cluster where the volumes are accessible on thelocal node only, the special cluster_tag of local is
used to indicate volumes that are not part of a Sun Cluster Resource Group or Disk Group.If "-L" is given as a the cluster_tag argument, then
iiadm lists all cluster tags associated with Point-in-
Time Copy. This option is invalid when used on a Solaris system on which the Sun Cluster package has not been installed or configured.-h
Prints the iiadm usage summary.
-v
Display the current version of the Point-in-Time Copy
software components. Contact Sun Enterprise Services for assistance in using the remaining commands in this section.-P delay unit volume_set
Alter the Point-in-Time Copy volume set tuning parame-
ters for the specified volume_set to delay ticks, every
unit I/O's. Delay ranges from 2 to 10000 inclusive; unit ranges from 100 to 60000 inclusive.
-R volume
After a volume has failed, Point-in-Time Copy places it
offline. After replacing the volume, place it back online using this option. Associated dependent volumesin the Point-in-Time Copy volume set are also placed
online. After the volume is placed online, this commandalso starts any necessary point-in-time volume updates.
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System Administration Commands iiadm(1M)
EXIT STATUS 0 Command completed successfully. >0 An error occurred.ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:_______________________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|________________________________________|
| Availability | storage/avs/point-in-time-copy, SUNWiiu|
|_____________________________|________________________________________|
| Interface Stability | Committed ||_____________________________|________________________________________|
SEE ALSO
dscfg(1M), svadm(1M), ds.log(4), rdc.cf(4), attributes(5), ii(7D), sv(7D)SunOS 5.11 Last change: 2 Oct 2007 16