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

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Using multiple FCoE uplink ports on each VC module connected to the HP 5900 and on each HP 5900 connected to the
Nexus allow dynamically distribution of the FCoE traffic across the ports using a round robin format.
FCoE Port Channeling increases the high availability and create enough FCoE SAN subscription.
Considerations
Enabling convergence in the extended network requires more careful bandwidth management than a Dual-Hop FCoE
topology. Suitable subscription is crucial to reduce the risk of congestion and slow performance, therefore the use of
Port Channeling is recommended.
The 5900AF-to-Nexus subscription is limited by the current Cisco NX software limitations, the ratio can go up to:
 1.25:1 with the Nexus 5500 series (can support a maximum of 8 ports per port-channel when carrying FCoE traffic)
 2.5:1with Nexus 5000 series (can support a maximum of 4 ports per port-channel when carrying FCoE traffic).
The server-to-VC uplink ratio is adjustable and can go up to:
 1.6:1 with the VC Flex-10/10D Module (10 FCoE ports max)
 4:1 with the VC FlexFabric Module (4 FCoE ports max)
 2:1 with the VC FlexFabric-20/40 F8 Module (8 FCoE ports max)
In addition to a more careful bandwidth management, Multi-Hop FCoE shared infrastructure requires also much more
attention, maintenance and upgrade practices, as these activities now have the potential to affect all traffic
(FC+Ethernet) in the data center.
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.
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 Nexus) 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 the Nexus is highly recommended.