R510 Fatal IO error !!

Hi,

We've recently deployed Dell R510 server which is randomly crashing and not showing much evidence of the crash in iDrac. Here is the servers specs :

2 x L5640
RAM 64GB
12x3TB Sata
HBA LSI-9211 Controller
OS : FreeBSD-10.2 

The crash event generated in iDrac only tells 'A Fatal IO error' and nothing else. Here is the screenshot of logged event :

http://prnt.sc/ats4ny