HP Virtual Connect: Common Myths, Misperceptions, and Objections, Second Edition

entire c-Class blade enclosure and makes it behave on the network like a single host running a

hypervisor.

#2: VC Ethernet is really a ProCurve switch and may not be

interoperable with 3rd party network switches

Incorrect: VC is not a ProCurve switch product and VC is interoperable with any other IEEE

compliant network device. VC is a product engineered, developed and sold by the HP BladeSystem

division independently of the HP ProCurve division. VC operates according to IEEE standards and,

like a ProCurve switch, will interoperate with any networking device that is also IEEE compliant.

Virtual Connect provides network-vendor-independent connectivity for an HP BladeSystem c-Class

enclosure.

#3: VC Ethernet doesn’t support Spanning Tree (STP)

Correct: Much to the delight of VC users, Spanning Tree support on VC is not needed. VC provides

HP server blade network connectivity just like a hypervisor provides virtual server network connectivity

and neither of these technologies require Spanning Tree support. VC doesn’t have to support

Spanning Tree just like hypervisor hosts don’t have to support it, yet both provide network redundancy

and load balancing. Just like a hypervisor host, VC provides network redundancy and load

balancing features that are modeled after NIC Teaming/bonding technology instead of switch

technologies like Spanning Tree. A Spanning Tree configuration error on any single switch in the

data center can negatively affect any other connected switch in the network, in addition to all servers

connected to the same network. With Virtual Connect, any redundancy and load balancing

configuration problems only affect a single blade enclosure

Fundamentally, VC doesn’t require support for protocols like STP because VC presents itself to the

network as a “termination endpoint”, as does a typical server or a hypervisor host. VC is not and

does not present itself as a “transit device”, as does a traditional switch.

(See response to question 32 for a discussion on loop avoidance.)

#4: VC can cause duplicate MACs and WWNs on the network.

Incorrect: Virtual Connect Manager (VCM) prevents duplicate MAC addresses and WWNs on the

network for servers in the same VC Domain and Virtual Connect Enterprise Manage (VCEM) prevents

duplicate MAC addresses and WWNs for servers across multiple VC Domains. Within a VC

Domain, all MACs and WWNs are restricted to a single server port at any one time. Regardless of

how physical servers are inserted, removed, swapped, or replaced, Virtual Connect prevents the

same Virtual Connect Managed MAC address or WWN from being used on more than a single NIC

or HBA port. A user could introduce duplicate MACs and WWNs on the network by improperly

selecting an address range already in use by another VC domain. To ensure that this problem does

not occur, customers have the option of using Virtual Connect Enterprise Manager (VCEM) to manage

up to 200 VC Domains

In addition ensuring that all VC managed MACs and WWNs are unique, VCEM also provides

automated server recovery and server movement across multiple VC domains.

within the data center.

Up to four enclosures if using VC enclosure stacking.

Up to 800 enclosures and 12,800 server blades