The enterprise SAN Fibre Channel Switch port calculation,  These are four Brocade switches per fabric based on the following formulae. Putting in that fourth Brocade Fibre Channel Switch  (FC-SW) means that you gain only 8 host connections from a 32 port Brocade FC switch.

 
One Switch

·         32 Total ports

·         4 ports reserved for port failure

·         28 ports remaining.

·         (int(28/5)) No more than 4:1 ratio, HOSTs : FA

·         23 Possible host connections

·         2 to support multi-pathing

·         11 total host connections

Two Switch

·         64 Total ports

·         4 ports reserved for port failure

·         4 ports reserved for E_ports

·         56 ports remaining.

·         (int(56/5)) No more than 4:1 ratio, HOSTs : FA

·         45 Possible host connections

·         2 to support multi-pathing

·         22 host connections (gain of 11)

 

Three switches

·         96 total ports

·         4 ports reserved for port failure

·         12 ports reserved for E_ports

·         80 ports remaining

·         (int(80/5)) No more than 4:1 ratio, HOSTs : FA

·         64 Possible host connections

·         2 to support multi-pathing

·         32 host connections (gain of 10)

 

Four switches

·         128 total ports

·         4 ports reserved for port failure

·         24 ports reserved for E_ports

·         100 ports remaining

·         (int(100/5)) No more than 4:1 ratio, HOSTs : FA

·         80 Possible host connections

·         2 to support multi-pathing

·         40 host connections (gain of 8)