Configure PFC on QFX5100 for RoCEv1

Good day, i try to configure PFC on two stacked QFX5100-48s-6q for SDS solution based on Microsoft S2D.

QFX Switches works on JunOS - 14.53, this firmware version supports only RoCE v1 ( MAC Based )

I have some questions:

1. By default switch have CoS\QoS rules, this working or need enable per interface?

2. I configured PFC with priority 5 eq 101 and see  this priority counters on the  switch ports. for test i limit speed for this priority to 1GB\s and simulate workload by livemigration.

On the server counters i see pause frames, but on the switch port MAC pause is zero and speed not limited.

my configuration is:

set protocols dcbx interface all dcbx-version ieee-dcbx
set protocols dcbx interface all priority-flow-control no-auto-negotiation
set protocols lldp interface all
set protocols lldp-med interface all

set class-of-service forwarding-classes class RDMA queue-num 5 no-loss
set class-of-service classifiers ieee-802.1 RDMA-class forwarding-class RDMA loss-priority low code-points 101 
set class-of-service congestion-notification-profile RDMA-CNP input ieee-802.1 code-point 101 pfc 
set class-of-service schedulers RDMA-SCHEDULER transmit-rate 1g 
set class-of-service schedulers RDMA-SCHEDULER shaping-rate percent 100
set class-of-service scheduler-maps lossless_map forwarding-class RDMA scheduler RDMA-SCHEDULER 

set class-of-service forwarding-class-sets RDMA-SET class RDMA
set class-of-service traffic-control-profiles RDMA-PROFILE scheduler-map lossless_map 
set class-of-service traffic-control-profiles RDMA-PROFILE guaranteed-rate percent 30
set class-of-service traffic-control-profiles RDMA-PROFILE shaping-rate percent 100 


set class-of-service interfaces xe-0/0/1 congestion-notification-profile RDMA-CNP 
set class-of-service interfaces xe-0/0/1 unit 0 classifiers ieee-802.1 RDMA-class 
set class-of-service interfaces xe-0/0/1 forwarding-class-set RDMA-SET output-traffic-control-profile RDMA-PROFILE
set class-of-service interfaces xe-0/0/2 congestion-notification-profile RDMA-CNP 
set class-of-service interfaces xe-0/0/2 unit 0 classifiers ieee-802.1 RDMA-class 
set class-of-service interfaces xe-0/0/2 forwarding-class-set RDMA-SET output-traffic-control-profile RDMA-PROFILE


set interfaces xe-0/0/1 ether-options no-flow-control
set interfaces xe-0/0/1 unit 0 family ethernet-switching interface-mode trunk
set interfaces xe-0/0/1 unit 0 family ethernet-switching vlan members S2D-Storage
set interfaces xe-0/0/2 ether-options no-flow-control
set interfaces xe-0/0/2 unit 0 family ethernet-switching interface-mode trunk
set interfaces xe-0/0/2 unit 0 family ethernet-switching vlan members S2D-Storage

 MAC statistics:                      Receive         Transmit
    Total octets                21862504642377   12048427320448
    Total packets                  14319156483       9995273862
    Unicast packets                14319043972       9982514122
    Broadcast packets                    44113          3520073
    Multicast packets                    68398          9239667
    CRC/Align errors                         0                0
    FIFO errors                              0                0
    MAC control frames                       0                0
    MAC pause frames                         0                0
    Oversized frames                         0
    Jabber frames                            0
    Fragment frames                          0
    VLAN tagged frames             14319150287
    Code violations                          0
  MAC Priority Flow Control Statistics:
    Priority :  0                             0                0
    Priority :  1                             0                0
    Priority :  2                             0                0
    Priority :  3                        192817                0
    Priority :  4                           754                0
    Priority :  5                           302          3264484
    Priority :  6                             0                0
    Priority :  7                             0                0

Please help to troubleshoot this problem, maybe I was wrong in the configuration!

Thx!