- play_arrow Overview
- play_arrow Storage Overview
-
- play_arrow Fibre Channel and FCoE-FC Gateways
- play_arrow Using Fibre Channel and FCoE-FC Gateways
- Understanding Fibre Channel
- Understanding an FCoE-FC Gateway
- Understanding Fibre Channel Fabrics on the QFabric System
- Configuring an FCoE-FC Gateway Fibre Channel Fabric
- Understanding FCoE-FC Gateway Functions
- Disabling the Fabric WWN Verification Check
- Understanding FCoE and FIP Session High Availability
- Understanding FIP Functions
- Understanding FIP Implementation on an FCoE-FC Gateway
- Understanding FIP Parameters on an FCoE-FC Gateway
- Configuring FIP on an FCoE-FC Gateway
- Setting the Maximum Number of FIP Login Sessions per ENode
- Setting the Maximum Number of FIP Login Sessions per FC Interface
- Setting the Maximum Number of FIP Login Sessions per FC Fabric
- Setting the Maximum Number of FIP Login Sessions per Node Device
- Monitoring Fibre Channel Interface Load Balancing
- Troubleshooting Dropped FIP Traffic
- Understanding Fibre Channel Virtual Links
- Understanding Interfaces on an FCoE-FC Gateway
- Example: Setting Up Fibre Channel and FCoE VLAN Interfaces in an FCoE-FC Gateway Fabric
- Configuring a Physical Fibre Channel Interface
- Converting an Ethernet Interface To a Fibre Channel Interface
- Configuring an FCoE VLAN Interface on an FCoE-FC Gateway
- Assigning Interfaces to a Fibre Channel Fabric
- Deleting a Fibre Channel Interface
- Troubleshooting Fibre Channel Interface Deletion
- Disabling VN2VF_Port FIP Snooping on an FCoE-FC Gateway Switch Interface
- Disabling Storm Control on FCoE Interfaces on an FCoE-FC Gateway
- Understanding Load Balancing in an FCoE-FC Gateway Proxy Fabric
- Defining the Proxy Load-Balancing Algorithm
- Simulating On-Demand Fibre Channel Link Load Rebalancing (Dry Run Test)
- Example: Configuring Automated Fibre Channel Interface Load Rebalancing
-
- play_arrow Data Center Bridging (DCBX, PFC)
- play_arrow Using Data Center Bridging (DCBX, PFC)
- Understanding DCB Features and Requirements
- Understanding DCBX
- Configuring the DCBX Mode
- Configuring DCBX Autonegotiation
- Disabling the ETS Recommendation TLV
- Understanding DCBX Application Protocol TLV Exchange
- Defining an Application for DCBX Application Protocol TLV Exchange
- Configuring an Application Map for DCBX Application Protocol TLV Exchange
- Applying an Application Map to an Interface for DCBX Application Protocol TLV Exchange
- Example: Configuring DCBX Application Protocol TLV Exchange
- Understanding CoS Flow Control (Ethernet PAUSE and PFC)
- Example: Configuring CoS PFC for FCoE Traffic
- play_arrow Learn About Technology
-
- play_arrow Configuration Statements and Operational Commands
Understanding OxID Hash Control for FCoE Traffic Load Balancing on Standalone Switches
The originator exchange identifier (OxID) field is one of several fields that the switch can use in its hash function computation for FCoE traffic load balancing over multiple outgoing links in an Ethernet link aggregation group (LAG) on ports that face an FCoE forwarder (FCF). The originator of an exchange between a pair of Fibre Channel (FC) endpoints (such as an FCoE host and an FC storage device) uses the OxID field as an identifier for that exchange. The originator also uses the OxID field to track the progress of the series of sequences that comprise the exchange.
When FCoE traffic traverses a LAG that faces an FCF, it can take multiple different links between the source and destination endpoints. The idea is to distribute the FCoE traffic across the FCF-facing LAG links, thus balancing the link load. The switch creates a hash value from some of the packet header fields, and uses the hash value to assign each packet to one of the LAG links. The switch always uses five packet header fields to compute the hash value:
Source ID (SID)
Destination ID (DID)
Fabric ID (FID)
Source Port ID (SPID)
Source Module ID (SMID)
In addition, the OxID field is included by default in the FCoE
load-balancing hash computation. However, if you do not want to use
the OxID field in the FCoE load-balancing hash computation, you can
remove it from the computation by using the set forwarding-options
hash-key family fcoe oxid disable command.
Including the OxID field in the load-balancing hash computation allows different exchanges between a pair of Fibre Channel (FC) endpoints (such as an FCoE host and an FC storage device) to take different paths across the network, thus improving the aggregate network throughput.
However, if the paths between different sets of FC endpoints have common links, congestion on one set of FC endpoints can affect the other set of endpoints. Such congestion can happen if the FCoE traffic on the two sets of endpoints uses the same priority (IEEE 802.1p code point). It is common for networks to use priority 3 (IEEE 802.1p code point 011) for FCoE traffic. However, you can assign different IEEE priorities to different lossless FCoE flows as described in Understanding CoS IEEE 802.1p Priorities for Lossless Traffic Flows to further separate the traffic flows.
