vsphere-esxi-vcenter-server-55-storage-guide

vSphere StorageUse the Predictive Scheme to Make LUN DecisionsWhen setting up storage for ESXi systems, before creating VMFS datastores, you must decide on the sizeand number of LUNs to provision. You can experiment using the predictive scheme.Procedure1 Provision several LUNs with different storage characteristics.2 Create a VMFS datastore on each LUN, labeling each datastore according to its characteristics.3 Create virtual disks to contain the data for virtual machine applications in the VMFS datastores createdon LUNs with the appropriate RAID level for the applications' requirements.4 Use disk shares to distinguish high-priority from low-priority virtual machines.NOTE Disk shares are relevant only within a given host. The shares assigned to virtual machines on onehost have no effect on virtual machines on other hosts.5 Run the applications to determine whether virtual machine performance is acceptable.Use the Adaptive Scheme to Make LUN DecisionsWhen setting up storage for ESXi hosts, before creating VMFS datastores, you must decide on the numberand size of LUNS to provision. You can experiment using the adaptive scheme.Procedure1 Provision a large LUN (RAID 1+0 or RAID 5), with write caching enabled.2 Create a VMFS on that LUN.3 Create four or five virtual disks on the VMFS.4 Run the applications to determine whether disk performance is acceptable.If performance is acceptable, you can place additional virtual disks on the VMFS. If performance is notacceptable, create a new, large LUN, possibly with a different RAID level, and repeat the process. Usemigration so that you do not lose virtual machines data when you recreate the LUN.Choosing Virtual Machine LocationsWhen you’re working on optimizing performance for your virtual machines, storage location is animportant factor. A trade-off always exists between expensive storage that offers high performance and highavailability and storage with lower cost and lower performance.Storage can be divided into different tiers depending on a number of factors:• High Tier. Offers high performance and high availability. Might offer built-in snapshots to facilitatebackups and point-in-time (PiT) restorations. Supports replication, full storage processor redundancy,and SAS drives. Uses high-cost spindles.• Mid Tier. Offers mid-range performance, lower availability, some storage processor redundancy, andSCSI or SAS drives. May offer snapshots. Uses medium-cost spindles.• Lower Tier. Offers low performance, little internal storage redundancy. Uses low end SCSI drives orSATA (serial low-cost spindles).30 VMware, Inc.