Useful commands you can run to gather vSAN & Storage related information for troubleshooting 

• uptime
• vmware -vl
• esxcli vsan cluster get
• esxcli vsan health cluster list
• esxcli vsan health cluster get -t=”Overall disks health”
• esxcli vsan storage list
• esxcli storage core device list
• esxcli storage core device stats get

Much of this is useful to send to VMware when raising an SR