Replication Configuration Wizard - Active-Active Remote Clone

Note:

GAD is only available on VSP G series because virtualized LDEVs are required.
Configuration or adoption of GAD cross-path scenarios requires CCI version 01-41-03/03 or greater to be installed on the ISM node.
Primary volumes must be set up within a host group prior to configuring a GAD replication using Protector.
GAD replications require the P-VOL and S-VOL to have matching virtual serial numbers and virtual LDEV IDs. Selecting Automatically Selected in the Configure Resource Group page of the wizard ensures this is done.
Any LUN path to the secondary volume will become inaccessible if the GAD replication is deleted from Protector (i.e. torn down). This occurs because the virtual LDEV ID is automatically deleted from the S-VOL, causing host I/Os to be rejected. To recover from this, either recreate the GAD pair (if the pair was deleted unintentionally) or assign a new virtual ID to the clone S-VOL

Figure. Replicate Configuration Wizard - Active-Active Remote Clone (Global-Active Device) - Configure Capacity Savings

Control	Description
Capacity Saving Mode	One of the following options: Match Source Volumes – When provisioning S-VOLs Capacity Saving will match the settings of the source volumed. Compression - When provisioning S-VOLs Compression will be enabled, the data compression function utilizes the LZ4 compression algorithm to compress the data. Deduplication and Compression - When provisioning S-VOLs Deduplication and Compression will be enabled. The data deduplication function deletes duplicate copies of data written to different addresses in the same pool and maintains only a single copy of the data at one address. None - When provisioning S-VOLs Capacity Saving will not be used
Capacity Saving Process Mode	Only available when a Capacity Saving Mode other than None is selected. Can be one of the following: Inline - When you apply capacity saving with the inline mode the compression and deduplication processing are performed synchronously for new write data. The inline mode minimizes the pool capacity required to store new write data but can impact I/O performance more than the post-process mode. Post Process - When you apply capacity saving with the post-process mode the compression and deduplication processing are performed asynchronously for new write data. Storage Default – match the default option set on the storage array. Match Source Volume – match the settings of the source volume.
Cancel	Discards all changes and reverts to the previous page.
Previous	Takes the user to the previous screen in the wizard.
Next	Takes the user to the next screen in the wizard.

Figure. Replicate Configuration Wizard - Active-Active Remote Clone (Global-Active Device) - Configure Pool etc.

Control	Description
Pool	Specifies the target storage pool from which replication LDEVs are allocated. Provides a list of available pools giving name and available space. Note: All replication types have pool except Asynchronous Remote Failover (Universal Replicator). Select a Dynamic Provisioning Pool. Note: Dynamic Provisioning Pools must be created using Storage Navigator prior to selecting the Target Storage/Pool in Protector.
Target Quorum	Selects the volume to use as the quorum disk. Note: A Quorum disk is required to manage each GAD replication pair. It is best practice to allocate a separate Quorum disk for each pair. Both Quorum and Quorum-less disks are available for selection.
Mirror Unit	The mirror unit number for the replication can be set to 0, 1, h1 or h2. Select Allocate Automatically to allow Protector to choose one.
Copy Pace	Determines how quickly the storage array copies data. The array’s default is Slow (3), Protector defaults to Medium (8).
Use Consistency Group	All P-VOLs in a replication are, by default, placed in the same consistency group to ensure consistency of data across all volumes. This option allows this behavior to be disabled.
Cancel	Discards all changes and reverts to the previous page.
Previous	Takes the user to the previous screen in the wizard.
Next	Takes the user to the next screen in the wizard.

Figure. Data Flow Wizard Hitachi Block Replication Configuration - Select Remote Path Group

Control	Description
Select Remote Path Group	Specifies the Remote Path Group to be used for the replication. Automatically Selected - Allows Protector to automatically select a Remote Path Group Note: For GAD it is recommended the user specifies a group to avoid sharing with other replications. User Selected - The user specifies the Remote Path Group. Warning: You cannot specify the "User Selected" option and select a path group with an ID of 0. To use a path group with an ID of 0, specify the "Automatically Selected" option. The path group with the lowest ID will be selected (which will be ID 0, if a path group with that ID exists). Remote path groups are listed in the format: Path Group Id: 0x51 Port Mappings: 5E <-> 3E The arrow depicts the direction of the path, either left to right or bidirectional. The arrows can also have a line through them depicting the path is currently broken. Only remote path groups that are suitable for the replication are displayed, for example for GAD only bidirectional path groups are listed.
Cancel	Discards all changes and reverts to the previous page.
Previous	Takes the user to the previous screen in the wizard.
Next	Takes the user to the next screen in the wizard.

Figure. Replicate Configuration Wizard - Configure Resource Group

Control	Description
Configure Resource Group	Specifies the resource group to be used for S-VOLs, in order to support snapshots and replications from VSM volumes (adding volumes to a VSM is performed by adding the volumes to the correct resource group). Note: If there are existing S-VOLs, then the resource group used by those will be selected. If the existing S-VOLs are in multiple resource groups or in a resource group that contradicts the user selection, then the operation will fail with an error. This setting should not be modified for existing replications. Automatically Selected - Allows Protector to automatically select a resource group in the following order of priority: If there are existing S-VOLs, then the resource group used by those will be selected. The resource group used by the P-VOLs, if the replication is in-system and the P-VOLs are all in one resource group. Resource group 0. Note: If existing S-VOLs are in multiple resource groups, then the operation will fail with an error. User Selected - The user specifies the Resource Group.
Cancel	Discards all changes and reverts to the previous page.
Previous	Takes the user to the previous screen in the wizard.
Next	Takes the user to the next screen in the wizard.

Figure. Replicate Configuration Wizard - Secondary Host Groups (GAD)

CAUTION:

If replication S-VOLs are exposed to a host, the user is responsible for ensuring they are not in use during replication resynchronization. Failing to do so may result in a critical failure of the host.

Note: Protector analyses the LUN IDs of the P-VOLs in all host group paths and, if consistent and available, uses these LUN IDs for all S-VOL host group paths either during initial set-up, mounting, or when adding additional LUNs on demand.

To provide a graceful fallback:

If the P-VOL LUN IDs are not consistent in all host group paths Protector will still use a consistent ID for S-VOL mappings, but these will not necessarily match any of the P-VOL LUN IDs.
If a P-VOL has a consistent ID in all host group paths, but this LUN ID is not available in all S-VOL host group paths then Protector will choose a different, consistent LUN ID for the S-VOL for all host group paths.
When not able to match LUN IDs with those used by P-VOLs and/or the S-VOLs, Protector chooses an unused LUN ID. In order to keep LUN ID’s compatible with VMware and Hyper-V when selecting LUN ID’s Protector will first attempt to select ID’s at or below 255. If this is not it will then attempt at or below 1024, followed by at or below 2048. Finally, at or below the array maximum. A warning will be displayed when an ID can not be found in a range.

Some systems expect LUN ID 0 to be used only as a boot volume. Protector will therefore only use LUN ID 0 for the S-VOL host group paths if the P-VOL LUN ID is 0.

Control	Description
Use Protector Provisioned Host Group	Protector will create a LUN path from each S-VOL it provisions in a placeholder host group. If this option is not selected, at least one Secondary Host Group must be specified below.
Enforce LUN ID Matching	For environments where LUN ID consistency is mandatory, selecting this option will cause the replication to fail if: The P-VOL does not have a consistent LUN ID in all host group paths. The P-VOL LUN ID is not available in all S-VOL host group paths.
Secondary Host Groups	Specify zero or more host groups that Protector will configure to provide access to the S-VOL(s) when configuring replication scenarios. If no host groups are specified here then Protector will place the S-VOL(s) in it's dummy host group. Click the Add Host Group button to insert another Host Group selection control. Click the Remove button next to a Host Group selection control to delete it. Note: If a LUN path to be created already exists, Protector will not attempt to add it again, or to change its ID. The specified host groups must be in the same resource group as the secondary volumes. For GAD replications, if the host group names and port IDs match between primary and secondary storage nodes, Protector will attempt to match the LUN IDs used for the S-VOLs with those of the respective P-VOLs. If this cannot be achieved then a warning will be logged and the next available LUN ID will be used. Tip: Use this option to specify host groups that enable access to S-VOL(s) when configuring GAD cross-path and multi-path and other replication scenarios where the S-VOL(s) will need to be accessed (e.g. during failover).
Cancel	Discards all changes and reverts to the previous page.
Previous	Takes the user to the previous screen in the wizard.
Next	Takes the user to the next screen in the wizard.

Figure. Replicate Configuration Wizard - Naming Options

Control	Description
Secondary Logical Device Name	Specifies how S-VOLs will be named: Match Origin - The S-VOL will be given the same name as that used for the origin P-VOL (i.e. the left-most volume in the data flow). Custom - The S-VOL will be named using the naming rule provided. The naming rule can consist of literal strings and/or one or more substitution variables listed. Click Display variables which can be used for the secondary LDEVs' name to view the available substitution variables: `%ORIGIN_SERIAL%` - S/N of leftmost array in data flow. E.g. output string: `210613` `%ORIGIN_LDEV_ID%` - ID of leftmost LDEV in data flow. E.g. output string: `00:3A:98` `%ORIGIN_LDEV_NAME%` - name of leftmost LDEV in data flow. `%PRIMARY_SERIAL%` - S/N of primary array in this operation. E.g. output string: `442302` `%PRIMARY_LDEV_ID%` - ID of primary LDEV in this operation. E.g. output string: `00:4C:EB` `%PRIMARY_LDEV_NAME%` - name of primary LDEV in this operation. `%SECONDARY_SERIAL%` - S/N of secondary array in this operation. E.g. output string: `356323` `%SECONDARY_LDEV_ID%` - ID of secondary LDEV in this operation. E.g. output string: `01:F4:35` `%CREATION_DATE%` - date secondary LDEV was created by this operation. E.g. output string: `20180427` `%CREATION_TIME%` - time secondary LDEV was created by this operation. 1130
Cancel	Discards all changes and reverts to the previous page.
Previous	Takes the user to the previous screen in the wizard.
Next	Takes the user to the next screen in the wizard.

Figure. Replicate Configuration Wizard - Active-Active Remote Clone (Global-Active Device) - Summary

Shows a summary of the replication configuration specified by the user.