[CentOS-virt] Using STP in kvm bridges

Wed Sep 16 10:53:15 UTC 2015
Dmitry E. Mikhailov <d.mikhailov at infocommunications.ru>

On 09/16/2015 03:27 PM, Dennis Jacobfeuerborn wrote:
> You should always enable STP on a bridge unless you have a very specific
> reason not to.
It's a question in the area of network adminisration.

STP is slow by today's standards - 50 seconds to wait until it 
rearranges the topology is too much. And RSTP isn't supported without a 
special daemon.

Next, if you want some physical link level redundancy you'd better go 
LACP - anyway almost every managed switch that has STP also has LACP 
today. And you can also get speed improvement.

Next, I doubt anyone would create two vNICs on a VM that connect to the 
same physical network. I see no point. The chances are they're going to 
be VLANs on a physical network. So you need VSTP. Does your switch do 
VSTP and are you up to configure it?

Thus personally I don't see a point in carelessly enabling STP on a 
hardware node.