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● 4G or 8G Fibre Channel SFP+ optics module and LC connectors over a distance of 4 km.
CAUTION:
Electrostatic discharge (ESD) damage can occur if the components are mishandled. Always wear an ESD-
preventive wrist or heel ground strap when handling the FC Flex IO module and its components.
WARNING: When working with optical fibres, follow all the warning labels and always wear eye protection.
Never look directly into the end of a terminated or unterminated fibre or connector as it may cause eye damage.
1.
● Position the optic so it is in the correct position. The optic has a key that prevents it from being inserted incorrectly.
● Insert the optic into the port until it gently snaps into place.
NOTE:
1. When you cable the ports, be sure not to interfere with the airflow from the small vent holes above and below the ports.
Processing of Data Traffic
The Dell Networking OS determines the module type that is plugged into the slot. Based on the module type, the software
performs the appropriate tasks. The FC Flex IO module encapsulates and decapsulates the FCoE frames. The module directly
switches any non-FCoE or non-FIP traffic, and only FCoE frames are processed and transmitted out of the Ethernet network.
When the external device sends FCoE data frames to the switch that contains the FC Flex IO module, the destination MAC
address represents one of the Ethernet MAC addresses assigned to FC ports. Based on the destination address, the FCoE
header is removed from the incoming packet and the FC frame is transmitted out of the FC port. The flow control mechanism is
performed using per-priority flow control to ensure that frame loss does not occur owing to congestion of frames.
Operation of the FIP Application
The NPIV proxy gateway terminates the FIP sessions and responses to FIP messages. The FIP packets are intercepted by the
FC Flex IO module and sent to the Dell Networking OS for further analysis. The FIP application responds to the FIP VLAN
discovery request from the host based on the configured FCoE VLANs. For every ENode and VN_Port that is logged in, the
FIP application responds to keepalive messages for the virtual channel. If the FC link becomes inactive or a logging off of
the switch occurs, the FIP engine sends clear virtual link (CVL) messages to the host. The FIP application also responds to
solicited advertisements from the end-device. In addition, the FIP application periodically sends advertisement packets to the
end-devices for each FCF that is part of the NPIV proxy gateway.
On FN IOM switches, you can configure the switch to operate in FIP Snooping or NPIV mode.
If the FN IOM Switch functions in the NPIV mode and you attempt to set the uplink port to be an FCF or a bridge port, a
warning message displays and the settings are not saved.
Operation of the NPIV Proxy Gateway
The NPIV application on the FC Flex IO module manages the FC functionalities configured in Dell Networking OS. After the FC
link comes up, the gateway sends the initial FLOGI request to the connected switch using the switch and port WWN methods.
After a successful login, the NPIV gateway sends a notification to inform the CNA that the FCF available to log in. The source
address of the FIP advertisement and FIP discovery advertisement response contain the MAC address of the FC Flex IO module
port. Depending on the number of login sessions on a particular FCF, the NPIV gateway can load-balance the login sessions from
ENodes.
The NPIV application performs the FLOGI to FDISC conversion and sends the new FC frame on the associated FC ports. After
the external switch responds to the FLOGI request, the NPIV gateway establishes the NPIV session and sends the frame to
the FIP application. The FIP application establishes virtual links to convert FCoE FLOGI accept messages into FIP FLOGI accept
messages. The corresponding ACL for the accept message is then applied. If a FIP timeout from ENode or VN_PORT occurs,
the NPIV application performs the FC fabric logout to the external FC switch. The NPIV application manages the sessions
between the FCoE and the FC domain.
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FC Flex IO Modules