Storage configuration planning

Complete all storage configuration planning tasks before you configure your Storwize® V3700 environment.

Planning the hosts

Host mapping provides a way for hosts to access specific logical units (LUs) within the storage systems. Determine:
  • For hosts that use a Small Computer System Interface (SCSI) over Fibre Channel connection, the worldwide port names (WWPNs) of the Fibre Channel (HBA) ports are on the hosts.
  • For hosts that use an Internet Small Computer System Interface (iSCSI) over Ethernet connection, the iSCSI qualified name (IQN) of the host and the authentication credentials.
  • The names to assign to the hosts.
  • The volumes to assign to the hosts.

Planning the volumes

An individual volume is a member of one storage pool and one I/O group. The storage pool defines which MDisks provide the back-end storage that makes up the volume. The I/O group defines which nodes provide I/O access to the volume. The management GUI provides a wizard to configure storage on the system, which results in a configuration to meet most requirements.

Before you create a volume, determine:
  • Whether to create the volume in image mode from a managed disk that contains data that must be preserved.
    Note: You can map the logical unit number (LUN) presented from an external storage system as an image mode managed disk. Then, you can migrate data from that volume onto the system.
  • The volume name.
  • The volume storage pool. For example, different storage pools might have different performance characteristics, depending on the storage that is contained by that storage pool.
  • The volume capacity.
  • Whether to provide extra redundancy by mirroring the volume across storage pools. For example, you might use the volume mirroring feature to provide redundancy across storage pools.
  • Whether to create fully allocated volumes or use thin-provisioned volumes.
  • Whether the cache mode for the volume is either readwrite, readonly, or none. The default is readwrite.

Consider the effect that FlashCopy® and thin-provisioned volumes have on performance. The effect depends on the type of I/O, and is calculated by using a weighting factor.