In discussing this to the Network Architech in my office - he has this to say:
I think some answers are here:
Since CCISS is a block driver, not a SCSI driver, that is why it
doesn’t use the regular /dev/sda /dev/sdb etc. names.
I think Rockstor may need to deal with the ! and convert them to /
like device-mapper-multipath had to do. Perhaps there is some kernel
reason for sysfs why they had to use ! in the sysfs names.
https://github.com/torvalds/linux/blob/master/Documentation/blockdev/cciss.txt