Posts tagged l2
Correction to L2 Forwarding Rules pos...
I posted here about the L2 forwarding rules when UCS is in EHV mode. Several readers have pointed out a flaw in the logic I posted, which was taken from Cisco’s DCUCI course. In Cisco’s defense, I did write that course.
At issue is how UCS deals with unknown unicast frames. The other post incorrectly states than an unkno [...]
UCS with disjointed L2 Domains
How do we deal with disjointed L2 domains in UCS?
To start, what’s a disjointed L2 domain? This is where you have two Ethernet “clouds” that never connect, but must be accessed by the same UCS Fabric Interconnect. Take, for example, a multi-tenant scenario where we have multiple customer’s servers within the same UC [...]
L2 Forwarding Rules in UCS EHV Mode
After a recent comment from @robertquast, it occurred to me that there’s quite a bit of confusion about the way that UCS Fabric Interconnects handle layer-2 forwarding in the default and recommended Ethernet Host Virtualizer mode.
The basic idea behind EHV is that the Fabric Interconnect appears to the upstream network as if it were a h [...]