Looks like you can get access to the raw device information from proc. You'll likely have to do your own discrete calculations with periodic samples to get the data rates. Here's the kernel documentation on /proc/net (section 1.4 of proc.txt).
https://git.kernel.org/cgit/linux/ke.../v3.19.2#n1017
That's for the latest 3.x kernel as of this writing but that interface does not change much across a lot of Kernel versions. I can only imagine it being possible. I don't have access to a SAN to verify as my system administration job has shifted into areas other than storage.
