Datasheet

Data Sheet
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Availability and Scalability
Superior resiliency for
higher server and
application availability
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The VBS is highly resilient. Each switch can operate both as master controller and as
forwarding processor. Each switch in the VBS can serve as a master, creating a 1:N
availability scheme for network control. In the unlikely event of a single-unit failure, all other
units continue to forward traffic and maintain operation.
High-availability features include the following:
●
Cross-switch EtherChannel provides the capability to configure Cisco EtherChannel
technology across different members of the VBS for high resiliency.
●
IEEE 802.1D Spanning Tree Protocol support for redundant backbone connections and loop-
free networks simplifies network configuration and improves fault tolerance.
●
Cisco UplinkFast and BackboneFast technologies help ensure quick failover recovery,
enhancing overall network stability and reliability.
●
IEEE 802.1s/w Rapid Spanning Tree Protocol (RSTP) and Multiple Spanning Tree Protocol
(MSTP) provide rapid spanning-tree convergence independent of spanning-tree timers and
also offer the benefit of Layer 2 load balancing and distributed processing. The VBS units
behave as a single spanning-tree node.
●
Per-VLAN Rapid Spanning Tree (PVRST+) allows rapid spanning-tree reconvergence on a
per-VLAN spanning-tree basis, without requiring the implementation of spanning-tree
instances.
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VLAN Trunking Protocol (VTP) pruning limits bandwidth consumption on VTP trunks by
flooding broadcast traffic only on trunk links required to reach the destination devices.
●
The trunk failover feature allows rapid failover to the redundant switch in the blade enclosure
if all uplinks from the primary switch fail. When the uplinks fail, the switch shuts down the
ports connected to the blade servers and lets network interface card (NIC) teaming software
direct traffic to the redundant switch. This feature is also known as link-state tracking.
●
Switch port autorecovery (Errdisable) automatically attempts to re-enable a link that is
disabled because of a network error.
●
Power and cooling resiliency are provided through redundant power and cooling capabilities
from the blade enclosure.
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Flexlink provides link redundancy with convergence time of less than 100 milliseconds (ms).
●
Cisco Hot Standby Router Protocol (HSRP) is supported to create redundant, fail-safe
routing topologies.
●
Unidirectional Link Detection Protocol (UDLD) and Aggressive UDLD allow unidirectional
links caused by incorrect fiber-optic wiring or port faults to be detected and disabled on fiber-
optic interfaces.
●
Switch-port autorecovery (Errdisable) automatically attempts to reactivate a link that is
disabled because of a network error.
●
Per-port broadcast, multicast, and unicast storm control prevents faulty servers from
degrading overall system performance.
●
Internet Group Management Protocol (IGMP) snooping provides fast client joins and leaves
of multicast streams and limits bandwidth-intensive video traffic to only the requestors.
●
Multicast VLAN registration (MVR) continuously sends multicast streams in a multicast VLAN
while isolating the streams from subscriber VLANs for bandwidth and security reasons.