Migration Scenario 2: Child pools do not exist on the system

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In this scenario, child pools do not exist on the system, so they must be created from existing parent pools, and assigned to an ownership group. Volume mirroring can be used to create a copy of the volume in the new child pool. The volume copy inherits the ownership group that was assigned to the child pool.

The following graphics show a configuration where child pools do not exist on the system and the process of assigning ownership groups. The first graphic represents the current configuration before ownership groups are assigned.

Figure 1. Example: Child pools are not configured on the system

In this example, the first graphic shows a system with two parent pools that contain two volumes each. Two volumes (vol0 and vol2) use a parent pool (pool0) and two other volumes (vol1 and vol3) use the other parent pool (pool1). The volume (vol0) is mapped to the host and is the source volume in a FlashCopy mapping with vol0 in pool1. In this case, you want to limit access to vol0 and vol1 and its related resources.

The second graphic shows the required steps to use ownership groups in this environment. First, two child pools are created from the parent pools. After the child pools are created, a mirrored copy of each volume is created in the new child pools. After the volume copies are in the corresponding child pool, the child pools are assigned to an ownership group and the volumes with those child pools inherit that ownership group. The original copy of the pool can be deleted from the parent pool. More resources can be added to the ownership group, such as hosts and host clusters. The last graphic in the sequence shows the new configuration.

Using the management GUI

To migrate ownership groups on a system without child pools, complete the following tasks:

Create child pools from existing parent pools:
1. In the management GUI, select Pools > Pools.
2. On the Pools page, right-click the pool that you want to create the child pool from and select Create Child Pool.
3. Repeat this step for all the pools that you want to use ownership groups. In the example, a separate child pool is created from both parent pools (pool0 and pool1).
Migrate volumes from parent pool to child pools:
1. In the management GUI, select Volumes > Volumes by Pools.
2. Select the parent pool that you created the child pool from, and then right-click the volume and select Add Volume Copy.
3. On the Add Volume Copy page, select the child pool that you want to copy the volume to and click Add.
4. If necessary, delete the original copy from the parent pool.
5. Repeat steps 2.b to 2.c for each volume.
Note: This process uses volume mirroring to create a copy of an existing volume in the child pool. You can also use the Migrate volume to another pool action.
Create ownership groups and assign child pools:
1. In the management GUI, select Access > Ownership Groups.
2. On the What is an Ownership Group? page, enter a name of the ownership group and select Create Ownership Group.
3. On the Create Ownership Group page, expand Child Pools and select Assign.
4. On the Assign Child Pools page, select the child pools that you want to add to the ownership group and click Assign.
5. If the system detects dependent resources for volumes that are within that child pool, the management GUI displays the Additional Resources to Add page. The page lists hosts or host clusters that have mappings to volumes that inherit the ownership group. For example, in the preceding graphic, child pool0 is added to the ownership group and vol0 automatically inherits the ownership group of child pool0. However, the host mapping between vol0 and host does not inherit the ownership group from vol0 because it also depends on the host. On the Additional Resources to Add, select the host or host clusters to add to the ownership group. Click Proceed.
6. On the Ownership Groups page, verify that child pool is assigned to the new ownership group.
7. Repeat steps 3.c to 3.f for any other child pool.
8. After you assign ownership groups to all child pools, create a user group to include users that are the owners of the ownership group. Select Access > Users and click Create User Group
9. On the Create User Group page, enter the following information:
  
  Name
  
  Enter the name of the user group.
  
  Role
  
  Select the role for all users within the user group. User groups that are assigned in ownership groups cannot use the Security Administrator role.
  
  Ownership Group
  
  Select the ownership group that you created earlier and assign it to this user group.
10. On the Access > Users page, select existing users or create new users to assign to the user group. These users automatically inherit the ownership group that is assigned to the user group. These users can now start creating objects like hosts and volumes within this ownership group, using capacity in the child pools that are assigned to the ownership group.

Using the command-line interface

To assign objects to ownership groups, complete these steps:

To create a child standard pool, enter the following command:
```
mkmdiskgrp -size 100 -unit tb -parentmdiskgrp name
```
where name is the name of the parent pool that provides the capacity for the child pool.
To create a child data reduction pool, enter the following command:
```
mkmdiskgrp -parentmdiskgrp data_reduction_parent_pool -datareduction yes -noquota
```
Where data_reduction_parent_pool is the name of the parent data reduction pool.
To create the ownership group, enter the following command:
```
mkownershipgroup -name name
```
where name is the name of the ownership group that you are creating.
To assign the child pool to the new ownership group, enter the following command:
```
chmdiskgrp -name name -ownershipgroup owner_name 
```
where name is the name of the child pool and owner_name is the name of the new ownership group.
To copy volumes that were in the parent pool to the new child pool, enter the following command:
```
addvolumecopy -pool storage_pool_name volume_name
```
where storage_pool_name is the name of the child pool. The volume_name parameter is the name of the volume that you are creating a copy of.
Note: This process uses volume mirroring to create a copy of an existing volume in the child pool. You can also use the migratevdisk command to migrate the volume to the new child pool.
After you assign ownership groups to all child pools, create a user group to include users that are the owners of the ownership group. To create a user group, enter the following command:
```
mkusergrp -name group_name -role administator -ownershipgroup owner_name
```
where group_name is the name of the user group and owner_name is the name of the new ownership group. User groups that are assigned to ownership groups cannot use the SecurityAdmin role.
Note: Do specify -remote yes for this user group. This value enables remote authentication with LDAP, which is not supported by ownership groups.
You can use either the mkuser command to create new users in the user group or use the chuser to assign existing users to the user group. Users inherit the ownership group that was assigned to the user group. These users can now start creating objects like hosts and volumes within this ownership group, using capacity in the child pools that are assigned to the ownership group.