I have netapps FAS2554 connected to switch with trunk port e0d and e0e both connected using 10 G port to a Brocade switch stack for a combined aggregate and two switch of exact same model on a stack for fail-over.
Recently, after the upgrade of ESX 6 when I logged a ticket with netapps they found CSC error on Nsanity report. The primary issue of storage has been fixed after the upgrade of 6. u1 ESX, however, the CSC error are stil there on e0e and e0d on both FAS2554 module.
After reviewing with Netapps they suggested that the failure could be cable or switch port, as they suggested that filer could have caused major issue then just generating CRC error that is not conceivable to the performance of storage.
I do not find any issue on switch and I do not see how I would multiple interface error with CRC, if there is a single cable issue and what are the chances of multiple cable issue and how it would continue to work without major performance degradation.
It is really hard to work with netapps support, as they would either ask for log after log in email or they will make assumption for other device fault without even doing proper diagnostic on netapps device