Check manual page of brocade_mlx_fan
Brocade NetIron MLX / ADX / FGS / ICX devices: Fans
Checks the operational status of fans in Brocade NetIron MLX / ADX /
FGS / ICX switching / routing devices.
Returns OK on status 2 (normal), CRIT on status 3 (failure)
and UNKN on every other status.
If a fan description is delivered by SNMP, the item is build from the
fan ID plus the description. Otherwise it is just the ID.
Finds one item per fan.