10.5 HP StoreVirtual Storage VSA Installation and Configuration Guide (TA688-96138, March 2013)

• Use of any Hyper-V Server configuration that Microsoft does not support.
• Booting physical servers off of a VSA cluster.
• Extending the data virtual disk(s) (ESX Server SCSI 1:x or in Hyper-V, the first SCSI Controller)
of the VSA while in a cluster.
• Co-location of a VSA and other virtual machines on the same physical platform without
reservations for the VSA CPUs and memory in ESX.
• Co-location of a VSA and other virtual machines on the same VMFS datastore or NTFS partition.
Hardware design for VSA
The hardware platform used for a virtual SAN affects the capacity, performance, and reliability
of that virtual SAN. The hardware features listed below affect the VSA configuration.
• CPU
• Memory
• Virtual Switch or Network
• Controllers and Hard Disk Drives
• Network Adapters
CPU
Because the CPUs of the VSA must be reserved, platforms that will host a VSA and other VMs
should be built with more processor cores to accommodate the additional VMs. Multi-core processors
with at least 2 GHz per core should be used so that two cores with at least 2 GHz can be reserved
for the VSA. All additional cores are then available for use with other VMs, thereby avoiding
resource contention with the virtual SAN. For example, a platform with two dual core processors
could host a VSA and use 3 cores to share for other VMs.
Memory
Similarly the memory of the VSA must be reserved. For platforms that will host a VSA and other
VMs, build in additional memory to accommodate the additional VMs. All system memory on the
host that is not used by the VSA can be used by other VMs
Virtual switch or network
The virtual switch or network should be entirely dedicated to the VSA and not used for any other
traffic.
Controllers and hard drives
The internal disk controller and actual hard disk drives of a platform affect the capacity and IO
performance of the VSA. Ideally VSAs should use storage that is hosted by many SAS or SCSI
drives. If you are designing a new server that will host VSAs, you should incorporate the following
recommendations.
• Use as many hard drives as the platform will allow and prefer faster rotation speeds. The more
hard drives and the faster their rotation speed, the more IOPs, and better performance.
• Select controllers with protected write cache and ensure that the write cache is enabled.
• Do not enable disk caching on servers that host VSAs.
Network adapters
The number of network adapters available in a platform affects your options for configuring virtual
switches. VSAs that will have a dedicated server platform only need two ethernet (minimum 1 GB)
22 Designing a virtual SAN