First published on TECHNET on Apr 15, 2011
Hi Everyone, this is Nitin Bhat and Hector Linares from the fabric management team in SCVMM. While talking with TAP customers we got some great questions that we wanted to share with you all.
·Q: How does the SMI-S connection occur between VMM2012 and the SAN array? In other words, what protocol is used and what access is required on the SAN?
A:CIM-XML is used to communicate with the underlying SMI-S providers. VMM never communicates with the SAN arrays themselves.
·Q: How to set up communication between SMI-S provider and the SAN?
A:SMI-S Providers are vendor specific. Each one will have a different setup process. At a high level, here are the series of steps.
1. Install SMI-S provider
2. Add array to the provider using SAN credentials
3. Add user account to the provider that will be used by VMM to access the provider
4. Add provider to VMM using credentials in #3
· Q:What kind of topology is supported?
A:Right now it is single machine. Providers are not HA capable. It is important to understand that an SMI-S provider is for management only and is not in the critical path for day to day array functionality. If the provider is down for any reason… the array continues to work. SAN admin tool will continue to work as well (unless of course you also use the SMI-S provider)
HP EVA provider is HA. If you start multiple instances it knows and only allows one active instance.
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Q:Are there any best practices for provisioning storage to the virtual hosts? I’ve been told that CSVs could create large disk queuing. Does SCVMM2012 have the ability to take small LUNs and combine them together into a larger volume (and present them to the hosts)?
A:VMM team will have more guidance/best practice around RC timeframe. This content is more of reference architecture for SANs, VMM, clusters, and SMI-S providers.
Windows + Hyper-V do not offer a native way to aggregate small LUNs and present them as a CSV (unlike VMware that supports this). So the CSV will have to be sized/designed for the expected workload.
· Q:Guidance around Storage Admins managing SAN’s to allow connections from the SMI-S providers?
A:Adding a storage array to an SMI-S provider will expose all of its pools and LUNs. SAN admin should know that upfront when setting up the SMI-S provider.
