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BP1024 Scaling and Best Practices for Virtual Workload Environments with the FS7500 5
Figure 1 Typical high level architecture of virtualized environment with unified storage
In SAN environments, also referred to as block based storage, VMware ESXi hosts use VMFS formatted
block volumes for datastores. Typically ESXi servers will connect to the storage via a SAN which will be
Ethernet based for iSCSI. The iSCSI I/O traffic would use the Multipath I/O (MPIO) stack on VMware
and a storage vendor specific plug-in can be implemented with VMware pluggable storage
architecture (PSA) to customize the MPIO functionality for particular storage architecture. EqualLogic
Multipathing Extension Module (MEM) is the EqualLogic aware specific plugin for VMware environment
deploying PS Series arrays. With block based SAN storage additional VMware features such as block
zeroing, full copy, and hardware assisted locking are enabled via VAAI (vStorage APIs for Array
Integration).
More information about VAAI is available at vmware.com: http://kb.vmware.com/kb/1021976.