Cisco UCS with Brocade Fabric
Recently we had a customer decide to use Brocade Fabric switches with their Cisco UCS environment. Typically UCS customers use Cisco MDS so this was a new endeavor for us. This blog addresses the high level options for implementing Brocade Fabric Switches with Cisco UCS each with pro’s and con’s. Enjoy after the jump.
UCS FC uplinks can be bound to vHBA’s by VSAN or Pining. Each has its pro’s and con’s.
· UCS is balanced (round robin FLOGI’s to each uplink)
· If a path fails round robin kicks in and FLOGI’s to next the uplink
· VSAN’s are “Best Practice” from Cisco
· Less configuration
· New uplinks can be added dynamically but the FLOGI’s will NOT redistribute immediately. A reboot of Blades is needed to redistribute over new FC uplink
· Direct control
· Servers per FC uplink can be managed
· If a path fails round robin does not happen. The link stays down until it is restored. This is an advantage to ensure QoS bandwidth per vHBA/Blade
Best practice for VSAN’s is a unique VSAN ID per uplink VSAN. Also the VSAN ID and the FCoE VLAN ID should not be the same. Remember VSAN’s should never be common between FI’s. Dual Fabric is the only way to go if you want to keep failover and controller port login balance.
Pinning and unique VSAN’s can co-exist. A Brocade switch upstream has completely no idea what a VSAN is. So realize that the VSAN is strictly taking place on the FI. For the Brocade upstream, VSAN 1 could be used but the best practice is to use unique VSAN’s.
For this customer we decided to use the VSAN method. The customer did not want to have to worry about manually failing back when paths go down. The VSAN method is also Cisco’s UCS best practice. Adding and removing uplinks is easy while pining can be challenging.
Unless there is a specific reason to use pining, we recommend following the Cisco best practice and use VSAN. Ease of use and low maintenance make it the better option. Thanks for reading!
by Dean Gagnon