Hit an issue today where VNXe array FC ports negotiate to L-port instead of F-port when Fill Word is set to Mode 3 (ARB/ARB then IDLE/ARB). Result – loss of connectivity on the affected link.
Recommended FC Fill Word for VNX/VNXe arrays is Mode 3. Generally it’s a good idea to set them according to best practice as part of each installation. Apparently, when changing Fill Word from legacy Mode 0 (IDLE/IDLE) to Mode 3 (ARB/ARB then IDLE/ARB) array might negotiate as L-port and FC path goes down.
Solution is to statically configure port as F-port in port settings.
Environment:
- Dell M5424 8Gb Fibre Channel Switch: Brocade FOS v7.2.1b
- EMC VNXe 3200: Block OE v3.1.1.4993502
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