resyncflash

The resyncflash command is a point-in-time copy of an existing FlashCopy pair that was established with the -record and -persist parameters.

The resyncflash command copies only the parts of the volume that changed since the last point-in-time copy.

Read syntax diagramSkip visual syntax diagramresyncflash  -dev  storage_image_ID  -tgtpprc  -tgtoffline  -tgtinhibit  -freeze  -record  -persist  -multinc -tgtse  -cp  -nocp  -seqnum  flash_sequence_num  -pmir no required preferred -resetreserve  source_volume_ID:target_volume_ID   ...   "-"

Parameters

When a FlashCopy pair is established with the -record and -persist parameters, the pair initially synchronizes. A record of all host write operations to the source is maintained in the source volumes. When the resyncflash command is specified on the FlashCopy pair, the new data that is written to the source is copied to the target. The parameters that you specify in this command replace the parameters that you previously specified for the existing relationship. To keep the -record and -persist parameters, you must specify these parameters in the resyncflash command.

-dev storage_image_ID
(Optional)The storage image ID consists of the manufacturer name, machine type, and serial number. The storage image ID is required if you do not specify a fully qualified ID for the source and target volume or do not set the devid variable in your profile or through the setenv command. The storage image ID is also required if HMC is aware of more than one storage image. Using the -dev parameter temporarily overrides any defined value for devid for the current command.
-tgtpprc
(Optional) Allows the FlashCopy target volume to be a remote mirror and copy source volume.
-tgtoffline
(Optional) Rejects the resyncflash command if the target volume is online for host system access. This parameter applies only to count key data (CKD) volumes.
-tgtinhibit
(Optional) Prevents host system write operations to the target volume while the FlashCopy relationship exists.
-freeze
(Optional) Starts the queue full condition for the source volume. During the queue full condition, the source volume reports a status of long busy. All writes to the source volume are queued by the host and are written after the queue full condition is reset. The queue full condition is reset by an extended long busy timeout condition. The timeout condition affects all FlashCopy source volumes that are contained within a respective logical subsystem and that are established or modified with this parameter.
Note: Use the chlss and the chlcu commands to modify the extended long busy timeout setting.
-record
(Optional) This parameter, without the -multinc parameter, creates a type 1 incremental FlashCopy relationship. The type 1 FlashCopy® records data changes on both the source and target volumes of the FlashCopy pair.

A single volume can be the source volume to up to 12 FlashCopy relationships, and these relationships can be any combination of normal, persistent, or incremental relationships. However, only a single type 1 incremental relationship can exist.

Select this parameter when you create an initial FlashCopy relationship that you later want to use with the resyncflash or reverseflash command. If the -multinc parameter is not selected, you can also use the setflashrevertible command.

When you select the -record parameter, the –persist parameter is automatically selected.

-persist
(Optional) Creates a persistent FlashCopy relationship in which the relationship remains after the copy completes and remains indefinitely until you enter a rmflash command against the FlashCopy pair. If this parameter is not specified, a normal FlashCopy relationship is created and is automatically removed after the copy completes.

A single volume can be the source volume to up to 12 FlashCopy relationships, and these relationships can be any combination of normal, persistent, or incremental relationships. However, only a single type 1 incremental relationship can exist.

See the -record parameter for a description of a type 1 incremental FlashCopy relationship and the -multinc parameter for a description of a type 2 incremental relationship.

When you select either the -record or the -multinc parameter, the persist parameter is automatically selected.

-multinc
(Optional) Creates a type 2 incremental FlashCopy relationship. The type 2 FlashCopy records data changes only on the target volume of the FlashCopy pair.

A single volume can be the source volume to up to 12 FlashCopy relationships, and these relationships can be any combination of normal, persistent, or incremental relationships. However, only a single type 1 incremental relationship can exist.

The type 2 FlashCopy allows for more than one incremental FlashCopy relationship from the same source volume. However, because the change recording is maintained only on the target volume, the type 2 FlashCopy can cause a performance impact as more type 2 FlashCopy relationships are added.

Select this parameter when you create multiple FlashCopy volume pairs with the same source volume that you want to use with the resyncflash and reverseflash commands. However, FlashCopy pairs that are established with this modified recording method cannot be used with the setflashrevertible command.

When you select the -multinc parameter, the -persist and -record parameters are automatically selected.
Note: Incrementing multiple relationships with the same source volume on a single command line (as shown below) is not currently supported:
resyncflash -multinc 0000-00ff:0200-02ff 0000-00ff:0400-04ff 0000-00ff:0600-06ff
Instead, you must issue the resyncflash commands separately. For example:
resyncflash -multinc 0000-00ff:0200-02ff
resyncflash -multinc 0000-00ff:0400-04ff
resyncflash -multinc 0000-00ff:0600-06ff 
-tgtse
(Optional) The target volume that you are designating for a FlashCopy relationship might be a space-efficient logical volume. An error message is generated if the target volume that you are using to create the FlashCopy relationship is a space-efficient volume and you do not specify this parameter.
-nocp
(Optional) Inhibits a background copy. Data is copied from the source volume to the target volume only if a track on the source volume is modified. The FlashCopy volume pair relationship remains indefinitely until it is broken by a rmflash command or until all tracks on the source volume are modified.
When the -tgtse parameter is specified and the -cp or the -nocp parameters are specified, the no background copy behavior is the default.
Note: You cannot use the -nocp parameter with the -cp parameter in the same command.
-cp
(Optional) Starts a background copy. When the -tgtse parameter is not specified and the -cp or the -nocp parameters are specified, the background copy behavior is the default.
Note: You cannot use the -nocp parameter with the -cp parameter in the same command.
-seqnum flash_sequence_num
(Optional) Associates the FlashCopy relationships that are established with the specified sequence number. You can use this sequence number as an identifier for a relationship or group of relationships. An example sequence number is 00010.
-pmir no | required | preferred
The Remote Pair Copy option that you want to use. The Remote Pair Copy option, sometimes called Preserve Mirror, preserves synchronous Metro Mirror pairs when the FlashCopy source and target volumes are both Metro Mirror primary volumes and both Metro Mirror secondary volumes on the same storage system. The FlashCopy operation is completed on both the local site and the remote site.
no
FlashCopy operations are not completed on the remote site. If the target volume is a Metro Mirror primary volume, the remote copy might temporarily change to the duplex pending state. no is the default if the -pmir parameter is not specified.
required
FlashCopy operations do not change the state of the Metro Mirror primary volume pair to duplex pending. Both the source Metro Mirror volume pair and the target Metro Mirror volume pair must be in the full duplex state.
preferred
Uses the Remote Pair Copy option for FlashCopy operations when possible. The Remote Pair Copy option cannot be used if the configuration is not correct or the state of the volume is not supported by this function.
Notes:
  • The -preferred parameter is only valid for DS8870 and earlier system types.
  • The -preferred parameter is not valid for targets which are also PPRC multi-target primaries.
-resetreserve
(Optional) Forcibly clears any SCSI reservation on the target volume and allows establishing of a FlashCopy relationship. The reservation is not restored after the relationship is established.
  • When this option is not specified and the target volume is reserved, the command fails.
  • This option is ignored if the target is a CKD volume; this option is applicable only for fixed block volumes.
source_volume_ID:target_volume_ID ... | -
(Required) Increments a FlashCopy relationship for the source and target volume pairs with the specified IDs. This parameter accepts fully qualified volume IDs, which include storage image IDs, or a shortened version without storage image IDs if the -dev parameter is specified or you specify a value for the devid variable in your profile file. You must separate multiple FlashCopy pair IDs with spaces.
A FlashCopy pair ID consists of two volume IDs, one designated as the source and the other as the target volume for a FlashCopy relationship. You must separate the two volume IDs of a FlashCopy pair ID with a colon and no space. The first volume ID is the source volume. The second volume ID is the target volume.
The volume ID is a 32-bit number that can be represented as four hexadecimal digits in the form of XYZZ, where:
X
The address group, 0–F.
XY
The logical subsystem number, 00 - FE.
ZZ
The volume number, 00 - FF.
The ellipsis (...) indicates that, optionally, you can specify multiple values. If you use the dash (-), the specified value is read from standard input. You cannot use the dash (-) while you are in the DS CLI interactive command mode.
Example of a fully qualified FlashCopy pair ID is IBM.2107-75FA120/0001:IBM.2107-75FA120/0004
An example of a shortened version is 0001:0004
An example of multiple pairs is 0001:0004 0003:00FF 0008:000C

Example: Copying parts of a volume pair that changed since the last point-in-time copy

 dscli> resyncflash –dev IBM.2107-75FA120 -freeze 0100:0200 
Output
Remote FlashCopy volume pair 0100:0200 successfully resynchronized.