Supporting Fibre Channel over Ethernet Traffic on the Cisco ACI Fabric
Cisco Application Centric Infrastructure (ACI) enables you to configure and manage support for Fibre Channel over Ethernet (FCoE) traffic on the Cisco ACI fabric.
FCoE is a protocol that encapsulates Fibre Channel packets within Ethernet packets, thus enabling storage traffic to move seamlessly between a Fibre Channel SAN and an Ethernet network.
A typical implementation of FCoE protocol support on the Cisco ACI fabric enables hosts located on the Ethernet-based Cisco ACI fabric to communicate with SAN storage devices located on a Fibre Channel network. The hosts are connecting through virtual F ports deployed on an Cisco ACI leaf switch. The SAN storage devices and Fibre Channel network are connected through a Fibre Channel Forwarding (FCF) bridge to the Cisco ACI fabric through a virtual NP port, deployed on the same Cisco ACI leaf switch as is the virtual F port. Virtual NP ports and virtual F ports are also referred to generically as virtual Fibre Channel (vFC) ports.
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In the FCoE topology, the role of the Cisco ACI leaf switch is to provide a path for FCoE traffic between the locally connected SAN hosts and a locally connected FCF device. The leaf switch does not perform local switching between SAN hosts, and the FCoE traffic is not forwarded to a spine switch. |
Topology Supporting FCoE Traffic Through Cisco ACI
The topology of a typical configuration supporting FCoE traffic over the Cisco ACI fabric consists of the following components:
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One or more Cisco ACI leaf switches configured through Fibre Channel SAN policies to function as an NPV backbone.
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Selected interfaces on the NPV-configured leaf switches configured to function as virtual F ports, which accommodate FCoE traffic to and from hosts running SAN management or SAN-consuming applications.
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Selected interfaces on the NPV-configured leaf switches configured to function as virtual NP ports, which accommodate FCoE traffic to and from a Fibre Channel Forwarding (FCF) bridge.
The FCF bridge receives Fibre Channel traffic from Fibre Channel links typically connecting SAN storage devices and encapsulates the Fibre Channel packets into FCoE frames for transmission over the Cisco ACI fabric to the SAN management or SAN Data-consuming hosts. It receives FCoE traffic and repackages it back to the Fibre Channel for transmission over the Fibre Channel network.
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In the above Cisco ACI topology, FCoE traffic support requires direct connections between the hosts and virtual F ports and direct connections between the FCF device and the virtual NP port. |
Cisco Application Policy Infrastructure Controller (APIC) servers enable an operator to configure and monitor the FCoE traffic through the Cisco APIC GUI, or NX-OS-style CLI, or through application calls to the REST API.
Topology Supporting FCoE Initialization
In order for FCoE traffic flow to take place as described, you must also set up separate VLAN connectivity over which SAN Hosts broadcast FCoE Initialization protocol (FIP) packets to discover the interfaces enabled as F ports.
vFC Interface Configuration Rules
Whether you set up the vFC network and EPG deployment through the Cisco APIC GUI, NX-OS-style CLI, or the REST API, the following general rules apply across platforms:
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F port mode is the default mode for vFC ports. NP port mode must be specifically configured in the Interface policies.
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The load balancing default mode is for leaf-switch or interface level vFC configuration is src-dst-ox-id.
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One VSAN assignment per bridge domain is supported.
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The allocation mode for VSAN pools and VLAN pools must always be static.
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vFC ports require association with a VSAN domain (also called Fibre Channel domain) that contains VSANs mapped to VLANs.