Dell EMC PowerStore Configuring Volumes 2.x June 2021 Rev.
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Contents Additional Resources.....................................................................................................................4 Chapter 1: Volumes....................................................................................................................... 5 Volumes in PowerStore appliances................................................................................................................................. 5 Thin provisioning...........................................
Preface As part of an improvement effort, revisions of the software and hardware are periodically released. Some functions that are described in this document are not supported by all versions of the software or hardware currently in use. The product release notes provide the most up-to-date information about product features. Contact your service provider if a product does not function properly or does not function as described in this document.
1 Volumes A volume is a single unit that represents a specific amount of storage. Volume storage resources provide hosts with access to general-purpose, block-level storage through network-based iSCSI, Fibre Channel, and NVMe-over-Fibre Channel connections. With volume storage, you can manage partitions of block storage resources so that host systems can mount and use these resources.
● There is no redirection between appliances in a cluster, meaning that I/O is sent to one of the two nodes that contains storage for the volume. Thin provisioning Storage provisioning is the process of allocating available drive capacity to meet the capacity, performance, and availability requirements of hosts and applications. In PowerStore, volumes and file systems are thin provisioned to optimize the use of available storage.
● Placement: You can place the volume in an appliance that is shown in the drop-down list, or allow the system to place the volume automatically. ● Associated Volume Group (optional) : Select which volume group you want to associate the volume with. ● Volume Protection Policy (optional): Select a protection policy that contains snapshot and replication rules applicable for the volume. You can add a protection policy after creating the volume.
Delete a volume Prerequisites Delete a volume only under the following conditions: ● The volume was used for testing purposes, and the tests have finished. ● The volume has been replicated to a different destination, and the source volume is no longer needed. ● You are trying to save space by deleting the volume and the data on that volume is no longer needed. CAUTION: Volume deletion is an irreversible operation.
Change a protection policy for a volume A protection policy establishes snapshot and data replication rules for data protection. You can change the protection policy assigned to a volume. About this task If the current policy assigned to the volume includes a replication rule, you can only change it to a policy with no replication rule (which will stop this volume's replication) or to a policy with a replication rule that uses the same remote system. Steps 1. Under Storage, select Volumes. 2.
2 Volume groups overview A volume group is a logical container for a group of volumes. A volume group provides a single point of management for multiple storage resources that work together as a unit. You can use volume groups to achieve the following: 1. A simpler and easier way to manage and monitor resources. 2. Maintaining consistency across multiple volumes.
Create a volume group Prerequisites All members of a volume group must be hosted from a single appliance. Steps 1. Under Storage, select Volume Groups. 2. Click Create. 3. On the Create Volume Group slide-out panel, enter the name of the volume group. Optionally enter a description and choose a protection policy to apply to all volumes within the volume group. NOTE: If you apply a protection policy to the volume group, you cannot override the protection for individual volumes within the group.
Add new volumes to a volume group Steps 1. Under Storage, select Volume Groups. 2. Click the check box next to the volume group to which you want to add volumes. 3. Select More Actions > Add New Volumes. NOTE: You can also open the Create Volumes for Volume Group slide-out panel via the Members tab of the volume group. 4. Enter the volume information in the Create Volumes for Volume Group slide-out panel: ● Name (or Prefix): When you create a single volume, this name is the name of the volume.
Remove a volume from a volume group You can remove a volume from an existing volume group. Removing a volume from a volume group can affect future operations on that volume and volume group. About this task These affected operations can include refresh, restore, and deletion operations as well as applying and deleting protection policies. Be aware of some conditions that apply when removing volumes from volume groups: ● The volume retains the protection policy of the volume group from which it is removed.
3 Hosts and host group configurations Host configurations are logical connections through which hosts or applications can access storage resources. Before a host can access storage, you must define a configuration for the host and associate it with a storage resource. You can pool individual hosts together into a host group. A host group is a collection of hosts that enables you to perform volume-related operations across all the hosts in the group.
Steps 1. Under Compute, select Hosts & Host Groups. 2. Click Add Host. 3. On the Host Details page, enter a name for the host and select the operating system. 4. On the Initiator Type page, select Fibre Channel, iSCSI, or NVMe. Review the prerequisites for the host connections. 5. On the Host Initiators page, select an initiator from the autodiscovered initiators list. 6. On the Summary page, review the host connection details, and click Add Host.
Configure CHAP authentication Challenge Handshake Authentication Protocol (CHAP) authenticates iSCSI initiators (hosts) and targets (volumes and snapshots) to expose iSCSI storage while ensuring a secure, standard storage protocol. About this task Without CHAP authentication, any host that is connected to the same IP network as the system iSCSI ports can read from and write to the system. If your system is on a public network, it is strongly recommended that you use CHAP authentication.
4 Data mobility for volumes and volume groups Start a migration session to move a volume or volume group to a different appliance. Topics: • • Migrate storage resources to another appliance Migrate vVols to another appliance Migrate storage resources to another appliance Use this feature to move volumes, volume groups, or vVols to another appliance in the cluster without any disruption to host I/O.
If a Rescan Host dialog box displayed, select the Yes, the associated hosts have been rescanned check box and select Start Migration if you have rescanned the associated hosts. If you have not rescanned the associated hosts, rescan them before continuing the migration. A Data Migration dialog box is displayed. 8. To start the migration, select Migrate Now. You can monitor the migration session under Migration > Internal Migrations.
5 Thin clones A thin clone is a read-write copy of a volume, volume group, or snapshot that shares blocks with the parent resource. Data available on the source at the moment of the thin clone creation is immediately available to the thin clone. The thin clone references the source snapshot for this data. However, data resulting from changes to the thin clone after its creation is stored on the thin clone. Changes to the thin clone do not affect the source snapshot.
Table 1. Thin clone terminology (continued) Term Definition source snapshot, because the new source snapshot must be in the same base volume, volume group, or storage container family.
Figure 1. Thin clone hierarchy 1. Volume1 2. Snapshot 1 3, Snapshot 2 4. Thin Clone1 5.
6. Snapshot 3 7. Thin Clone3 8. Refresh The base volume family for Volume 1 includes all the snapshots and thin clones that are shown in the diagram. For Thin Clone 2: ● The family is Volume 1. ● The parent is Snapshot 2. ● The source is Snapshot 2. For Thin Clone 3: ● The family is Volume 1. ● The parent is Snapshot 3. ● The source is Snapshot 3. Now, if Thin Clone 3 is refreshed from Snapshot 1: ● The family is still Volume 1.
6 Performance policies A performance policy specifies I/O performance requirements for PowerStore storage resources. PowerStore provides three pre-defined performance policies: ● High ● Medium (default) ● Low PowerStore has share-based QoS. Share-based QoS means when there is contention at system level, a volume with a high-performance policy services more IOPS than a volume with a medium-performance policy.
