HP Virtual Connect Multi-Enclosure Stacking Reference Guide
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The first Virtual Connect domain created on the first enclosure will become the Base Enclosure. Remote Enclosures will
then be imported into the Base Enclosure Virtual Connect Domain. The base enclosure will contain the primary and
secondary Virtual Connect Manager instances. The base enclosure “role” cannot be transferred to another enclosure in
the stack. If the base enclosure (or its VC modules running the management application) is powered off, the other
enclosures will remain functional and connected assuming the VC networks have usable uplinks in the remaining
enclosures. The Virtual Connect Manager application will not be accessible until the base enclosure is powered back on.
All OA’s and Virtual Connect modules for each enclosure to be managed must be on the same IP subnet.
When designing a solution, the principles you apply to a single enclosure domain should be applied to a ME stacked
domain in the same way. For example, if you are building clusters of servers and you consider making your clusters span
multiple enclosures with single enclosure domains in order to be able to shut down an enclosure entirely and still have
the cluster up and running, you should make your clusters span multiple ME Stacked Domains as well. Do not put all the
servers of a cluster into different enclosures of one ME Stacked Domain if you wouldn’t want to put them into a single
enclosure.
As another example, do not make a ME Stacked Domain with enclosures in 2 different datacenters in an attempt to build
a disaster recovery solution. If a disaster hits the datacenter where the primary enclosure is located, you would not be
able to recover server profiles from the primary enclosure and you would not be able to manage Virtual Connect in the
remaining datacenter.
It is important that the IP subnet you plan on using for OA and VC traffic is not over utilized. Virtual Connect Manager
relies on LAN connectivity between the Onboard Administrators to provide management and control in a multi-enclosure
Virtual Connect domain. This connection ensures the configuration settings of the distributed modules remain in sync.
HP recommends isolating the management network from other networks to ensure that the communication integrity
remains intact.
HP only supports importing remote enclosures that do not have an existing domain configuration. Importing remote
enclosures with an existing domain will have the remote enclosure’s configuration erased. Merging of domains is not an
available feature.
Virtual Connect Fibre Channel does not support ME Stacking using the physical uplink port connections. All enclosures in
a single stack must have the identical VC-FC, VC Flex-10/10D and VC FlexFabric module placement and configuration in
each enclosure.
Important: Additional guidelines and configuration rules will be found in the document
titled “HP Virtual Connect for c-Class BladeSystem Setup and Installation Guide
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When to choose Multi-Enclosure Stacking
Here are some criteria that can be used to determine if you should use Multi-Enclosure Stacking:
If the 10Gb ports in the core switches are at a premium, you can reduce the number of ports required to
connect your servers by consolidating uplinks over up to 4 enclosures. Of course the tradeoff is that the overall
bandwidth between the enclosures and the core network would be reduced.
If the applications running on the servers generate a lot of traffic between themselves, but not so much
towards the core network, you could use Multi-Enclosure stacking to keep that traffic between up to 4
enclosures without going to the core switches.
If you have a small environment with 4 enclosures or less and you want to consolidate the management of
your Virtual Connect environment without implementing Virtual Connect Enterprise Manager, you can use
Multi-Enclosure Stacking to create a single Virtual Connect domain.
At the opposite end, if you have a large environment with more than 250 Virtual Connect-enabled enclosures,
you can use Multi-Enclosure Stacking to group these enclosures in domains of 2, 3 or 4 enclosures to stay
below the supported limit of 250 Virtual Connect domains per Virtual Connect Enterprise Manager server.
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http://h18004.www1.hp.com/products/blades/components/c-class-tech-installing.html