Monitoring and Managing SAN Storage
The esxcli storage san commands help administrators troubleshoot issues with I/O devices and fabric, and include Fibre Channel, FCoE, iSCSI, SAS protocol statistics. The commands allow you to retrieve device information and I/O statistics from those device. You can also issue Loop Initialization Primitives LIP to FC/FCoE devices and you can reset SAS devices.
For FC and FCoE devices, you can retrieve FC events such as RSCN, LINKUP, LINKDOWN, Frame Drop and FCoE CVL. The commands log a warning in the VMkernel log if it encounters too many Link Toggling or frame drops
To retrieve and reset the IO Device Management module
esxcli storage san fc events get
esxcli storage san fc events clear --adapter adapter