If you scan the bill of materials for the various Cisco UCS VSAN ReadyNodes you’ll see a line item for:
Controller Cache: Cisco 12Gbps SAS 1GB FBWC Cache module (Raid 0/1/5/6)
If you’ve followed Virtual SAN for awhile you might wonder, why would the ReadyNodes include controller cache when VMware recommends disabling controller cache when implementing Virtual SAN. Well, it turns out that the presence of the FBWC Cache module allows the queue depth of the Cisco 12G SAS Modular Raid Controller to go from the low 200’s to the advertised 895. The minimum queue depth requirement for Virtual SAN is 256 so including the FBWC Cache module allows the queue depth to increase above that minimum requirement and improve Virtual SAN performance.
Today I was working with Cisco to setup UCS C240 servers for Virtual SAN. As part of the process we needed to verify the Cisco 12G SAS Modular Raid Controller had the correct Firmware Version.
First we went to the VMware Compatibility Guide for Virtual SAN, navigated to the bottom of the page to the link for Build Your Own based on Certified Components. Under “Search For:” we selected “I/O Controller” and under “Brand Name:” we selected “Cisco” and found the listing for the Cisco 12G SAS Modular Raid Controller. It requires Firmware Version 4.270.00-4238.
Next we went into the Cisco UCS Manager and navigated to the Host Firmware Packages and found that the Storage Controller Firmware Package was 24.7.0-0047.
Through UCS Manager there is no way to get the I/O Controller Firmware Version. So, we had to reboot the host and hit “CTRL-R” to get into the Cisco 12G SAS Modular Raid Controller Bios Configuration Utility.
From here we hit CTRL-N to get into Properties.
On this screen you can see:
FW Version: 4.270.00-4238
Thus, we were able to confirm that we had the correct Firmware on the I/O Controller. If the FW Version was different than what VMware Virtual SAN supports, you would need to download the correct Firmware Package from Cisco and upgrade.
I hope this helps others save time trying to verify Firmware Versions. Thanks to my VMware Virtual SAN colleague, David Boone, who did most of the work that led to this post and our friends at Cisco for being a great partner and helping navigate UCS Manager and grabbing screenshots.