Reference:
https://downloads.dell.com/manuals/all-products/esuprt_solutions_int/ esuprt_solutions_int_solutions_resources/s-solution-resources_white-papers108_en-us.pdf (9)

Document: docu71319_dell-emc-unity-high-availability-a-detailed-review.pdf Page: 20 FAIL SAFE NETWORKING (FSN) Dell EMC Unity OE version 4.2.1 introduces Fail Safe Networking (FSN). FSN is a high availability feature that extends link failover into the network by providing switch-level redundancy. FSN appears as a single link with a single MAC address and potentially multiple IP addresses. FSN can consists of Ethernet ports, link aggregations, or any combination of the two. FSN adds an extra layer of availability to link aggregations alone as link aggregations provide availability in the event of a port failure while FSN provides availability in the event of a switch failure. Each port or Link aggregation is considered as a single connection and only the primary port or link aggregation in an FSN is active at a time. All ports in an FSN must have the same MTU size, but the speed and duplex settings can vary.

Explanation/Reference: https://www.delltechnologies.com/resources/en-us/asset/white-papers/products/storage/ h16289-dell_emc_unity-dynamic_pools.pdf (5)

Explanation/Reference: https://downloads.dell.com/manuals/all-products/esuprt_solutions_int/ esuprt_solutions_int_solutions_resources/s-solution-resources_white-papers108_en-us.pdf (9)