Very poor SAN performance on Cisco UCS B200 M3 Blades.
Deploying VMs from templates and cloning VMs hang.
CPU stats in a VM indicated 100% cpu in wio state
Cisco UCS provides a QoS feature to allow prioritization of certain types of traffic.
Cisco UCS supported multi-hop FCoE from release 2.1 onwards.
Enable Packet Drop (no pause) for any enabled priority (in my case below, it was Platinum) when using UCS 2.1+ i.e. UCS with multi-hop FCoE. This was not required in earlier versions of UCS using native FC.
I am not a networking expert to provide much clarity here, but according to Jeremy Waldrop, packet drop cannot be enabled on 2 different QoS groups on the same interfaces. I thought this wouldn’t matter because the QoS groups are assigned to different CoS groups, but I don’t know much about this to discuss further.
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