Avalanche: Cyberflood: Physical Link shows Local Fault when FEC is turned to auto?

Avalanche: Cyberflood: Physical Link shows Local Fault when FEC is turned to auto?

FEC is validated once the test is started, because it is at this point that the FPGA modules get reprogrammed and the FEC feature becomes active. If the testing ports from a NIC-64/NIC-67 (100G) are connected to a managed switch and the physical link shows as DOWN but fibers are connected, you should definitely check that FEC Configuration is not the cause for the problem, as sometimes this can be the cause for the Link Local Layer not coming up correctly and showing as if there would be a problem with the physical connection. IMPORTANT NOTE: FEC configuration should be checked on both sides, VIAVI Chassis on one side and Switch (DUT) side as well. By default the VIAVI chassis (testing ports) has the FEC configuration set to AUTO. If the FEC option is turned OFF in the C200/C100-S3 chassis, then the FEC feature needs to be turned OFF in device that the Chassis is connected to (DUT/Switch). Most of the times by disabling FEC on both sides (DUT & VIAVI Chassis) helps to recover from this faulty state. HOW TO VALIDATE THE FEC CURRENT STATUS ON A VIAVI CHASSIS You can also validate the status of the FEC option when you perform an SSH session to your chassis with the default credentials of admin/spt_admin. Then you need to issue the command "fec" to get the status of the FEC option. As we show you below: HOW TO VALIDATE THE FEC CURRENT STATUS ON A CISCO NEXUS NETWORK SWITCH You can verify if the Cisco Nexus Switch has this parameter configured by running the following commands: • # error-correction encoding reed-solomon • # shutdown • # no shutdown IMPORTANT: Make sure to restart the switch port for changes to take effect, with SHUTDOWN and then NO-SHUTDOWN on every network port in the setup.  HOW TO VALIDATE THE FEC CURRENT STATUS ON AN ARISTA NETWORK SWITCH --> To be confirmed and documented here. HOW DOES IT LOOK LIKE WHEN FEC CONFIGURATION IS NOT WORKING ON EITHER SIDE (VIAVI CHASSIS OR SWITCH) You would see that ports are not coming up and they show as LOCAL FAULT, See below for an example: admin> status Product                : C100-S3 Active Version         : 5.33.0143 Hypervisor Version     : 1.5.0 Device (IPv4) admin    : 172.18.21.53 255.255.255.0, Gateway: 172.18.21.1 (static) Serial number          : 7-615946A3 Standby Version        : 5.33.0143 Part Number            : 80-002523 REV J admin> linkstat Active Profile: L4L7-Functional-4x100G Port 1: 05:00.0 Type: NIC-64/67 Media: 850nm VCSEL Speed: 100G Link: Local Fault  Port 2: 05:00.0 Type: NIC-64/67 Media: Copper Cable Unequalized Speed: 100G Link: Up  Port 3: 85:00.0 Type: NIC-64/67 Media: 850nm VCSEL Speed: 100G Link: Local Fault  Port 4: 85:00.0 Type: NIC-64/67 Media: Copper Cable Unequalized Speed: 100G Link: Up  Another Example:  The 100G NIC-67 FEC is only enabled/used when the/an actual test starts  --- • admin> fec auto, (this means the FEC is off, and when a test starts, the driver checks and if the link is down the, the driver will send FEC packets. This is the default mode, and please note, the link will NOT come up until the AVC test is started.   • admin> fec on, the driver will always send FEC packets.   • admin> fec off, the driver will never send FEC packets.   Note : Please note any changes to the FEC setting only take affect after the test starts.