Hi,
I have some of S6720-30C-EI-24S-AC in my network and I have no problems sampling sflow in all ports in inbound direction.
I haven't noticed any performance degradation so far.
Port on slot 0 Information:
Interface: XGE0/0/1
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/2
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/3
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/4
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/5
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/6
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/7
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/9
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/10
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/11
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/12
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/13
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/14
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/15
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/16
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/17
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/18
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/19
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/20
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/21
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/22
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/23
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: XGE0/0/24
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN
Interface: 40GE0/0/1
Flow-sample collector: 1 Counter-sample collector : 1
Flow-sample rate(1/x): 1024 Counter-sample interval(s): 30
Flow-sample maxheader: 128
Flow-sample direction: IN