FCoE Cookbook for HP Virtual Connect Version 4.20 Firmware Enhancements May 2014

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Benefits
This scenario can be used to simplify third-party interoperability concerns in environment where different types of Fibre
Channel switches are used (i.e. when connecting HP5900 switches to a Cisco Fibre Channel switch like a MDS SAN switch)
because in NPV mode, the switch does not participate in domain operations or perform local switching. This enables
multivendor topologies to be implemented without the restrictions the FCF mode requires.
In NPV mode, fabric logins are passed upstream from the edge switch to the core MDS switch. The 5900 acts as a pass
through switch and converts the Fabric Login (FLOGI) command to a Fabric Discovery (FDISC) command and passes it to
the upstream SAN switch.
The use of multiple FCoE uplink ports on each VC module connected to the 5900 allows dynamically distribution of the
FCoE traffic across the ports using a round robin format.
By providing ability to define multiple FCoE VLANs on a single set of uplinks, VC allows multi-VSAN capability to be
enabled on the 5900 switches. The use of VSANs can help to maintain separation and traffic isolation to the servers on
the NPV switches since zoning is not supported. On the MDS side, zoning can be set to “extend” those VSANs to defined
MDS zones that are connected to different storage targets.
Considerations
In NPV mode, the switch does not operate as a typical Fibre Channel switch, fabric services (i.e. Name Service, Fabric
Login, zoning, etc.) are not available and Fibre Channel switching is not performed: all traffic is switched upstream in the
core switch.
The NPV mode uses N Port ID Virtualization (NPIV) technology, F_Ports that normally connect to the fabric are
configured in this mode as NP_Ports and use NPIV to register multiple WWPNs to the F_Port on the other end.
Multiple VSAN support
The number of FCoE networks per Shared Uplink Set is limited to 32. VSAN tagging is not supported for native FC fabrics.
The number of FCoE networks is additionally limited by the 1000 network domain limit.
For this feature to successfully integrate with HP 5900 switches, it is important to note that for each FCoE VLAN a unique
FC VSAN must be created and association between the two must be strictly configured as 1-to-1. Mapping of a single
VLAN into multiple VSANs is not supported.
All of the FCoE networks will share the same lossless Priority Flow Control (PFC) queue on any specific shared uplink set.
Sharing PFC queue between multiple VSANs will make it possible that traffic from one VSAN may have impact on traffic
from other VSANs. For that reason, it is highly recommended to create enough SAN subscription (i.e. by using a suitable
number of uplink between VC and 5900 but also between 5900 and Cisco MDS) to avoid any over-subscription issues
that would prevent SAN to pause and therefore to impact other VSANs. Therefore the use of multiple ports between the
5900 and MDS switches is highly recommended.