Transfer SnapMirror workflow

Goal

The Transfer SnapMirror workflow enables you to start an initialization or update transfer of data from a source volume to a destination volume in a SnapMirror or SnapVault relationship.

Prerequisites

 

·         You must be running Data ONTAP 8.2 or later on the affected cluster.

·         A SnapMirror or SnapVault relationship must exist between the source and destination volumes.

About this workflow

The Transfer SnapMirror workflow is executed to start a transfer of data between a source volume and a destination volume that are in a SnapMirror or SnapVault relationship. This transfer can either be an initialization transfer, in which all data from the source volume is transferred to an initially empty destination volume, or it can be an update transfer, in which only data that has been changed after the previous transfer is transferred to the destination volume.  Scheduled update transfers on a SnapMirror or SnapVault relationship cannot begin unless the destination has been explicitly initialized by this workflow or by some other operation.

WFA user actions

 

1.       Click Portal > Data Protection > Transfer SnapMirror to display the Executive Workflow dialog box for the Transfer SnapMirror workflow.

2.       Specify  the appropriate values for the following mandatory inputs:

o   Destination cluster

o   Destination storage virtual machine (SVM)

o   Destination volume

3.       Specify, if applicable, appropriate values for the following optional inputs:

o   Transfer Priority

o   Max Transfer Rate

o   Source Snapshot

4.       Click Execute.

WFA User input descriptions

The mandatory and optional user inputs for the Transfer SnapMirror workflow are described below.

Input

Description

Destination Cluster

(mandatory)

The name of the cluster in which the destination volume of the SnapMirror or SnapVault relationship resides

Destination Storage Virtual Machine Name

(mandatory)

The name of the SVM in which the destination volume of the SnapMirror or SnapVault relationship resides

Destination Volume

(mandatory)

Destination volume associated with the SnapMirror or SnapVault relationship.

Transfer Priority

(optional)

Priority at which the transfer runs. The default value is the value specified in the SnapMirror policy associated with the SnapMirror or SnapVault relationship.

Max Transfer Rate

(optional)

Maximum transfer rate, in kilobytes per second, at which data is transferred. The default (0) is unlimited, which permits the SnapMirror or SnapVault relationship to fully utilize the available network bandwidth.

Source Snapshot

(optional)

Snapshot copy on the source volume to use for the initialize or update transfer. This input affects the transfer operation in different ways depending on whether the relationship is SnapMirror or SnapVault, whether the transfer is an initialization or update, and whether the source volume type is read/write or data protection. See “Transfer operation behavior” below for details.

 

 

Snapshot copy transfer behavior

Depending on the relationship type, transfer operation type, or source volume type, your input or omission of input to the Source Snapshot field affects the transfer operation behavior in the following manner:

SnapVault relationship Snapshot copy transfer behavior

Transfer Operation

SnapVault behavior when source is read/write

SnapVault behavior when source is Data Protection (DP)

Initialize

·         If no source Snapshot copy specified, creates a new Snapshot copy and transfers it.

·         If a source Snapshot copy is specified, transfers the specified Snapshot copy.

Transfers the last exported Snapshot copy.

Source Snapshot copy specification is not supported for data protection volumes.

Update

·         If no source Snapshot copy specified, transfers only labeled Snapshot copies, as specified in the policy.

·         If a source Snapshot copy is specified, transfers only the specified Snapshot copy.

Transfers the last exported Snapshot copy.  

Source Snapshot copy specification is not supported for data protection volumes.

 

SnapMirror relationship Snapshot copy transfer behavior

Operation

SnapMirror behavior

SnapMirror behavior when relationship is second hop in a SnapMirror to SnapMirror cascade

Initialize

·         If no Snapshot copy is specified, creates a new Snapshot copy and transfers it and all Snapshot copies created prior to the new Snapshot copy.

·         If a Snapshot copy is specified, transfers all Snapshot copies on the source, up to the specified Snapshot copy.

Transfers all Snapshot copies from the source.

Source Snapshot copy selection is not supported for data protection volumes.

Update

·         If no Snapshot copy is specified, creates a new Snapshot copy and transfers it and all Snapshot copies created prior to the new Snapshot copy.

·         If a Snapshot copy is specified, transfers all Snapshot copies on the source, up to the specified Snapshot copy.

Transfers all Snapshot copies.  

Source Snapshot copy selection is not supported for data protection volumes.

 

Workflow sequence

 

When completing the Transfer SnapMirror workflow, WFA executes the following sequence of tasks:

 

1.       Transfer SnapMirror. WFA calls the Transfer SnapMirror command to trigger the initialization or update transfer to the destination volume of a SnapMirror relationship. By default, an initialization transfer is triggered, but if initialization has already been performed then an update transfer is triggered.

Result

 

After the Transfer SnapMirror workflow is successfully completed, an initialization or update transfer of data from source volume to destination volume is initiated in a SnapMirror or SnapVault relationship.

Workflow customizations

 

If you want to customize this workflow to await the end of initialization or update transfer operations, you can do so by inserting a command to pause the workflow until the update transfer operation is complete.