[DCB PFC]sharing command about how to check PFC has taken effect.

we always configure PFC on CE switch to ensure on packets were lost in the network, PFC is also called Per Priority Pause or Class Based Flow Control (CBFC). It enhances the Ethernet Pause mechanism. PFC is a kind of flow control mechanism based on priority. after we configured PFC, if the remote side reachs the bottleneck of the performance, the remote side will send pause frame to CE switch, and CE switch will also send pause frame to upsteam device, so that the upsteam device will stop sending traffic. below command can ceck if CE receive pause frame or send pause, and also can see which queue is enable for PFC. if it has the received counter and transmitted counter, it means the PFC has already take effected.

[~huawei]disp  dcb pfc interface 40ge  1/0/1

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Interface         Queue         Received(Frames)      Transmitted(Frames)     

-------------------------------------------------------------------------------

40GE1/0/1             3               1300155922               6073564133

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[~8006a-v-dsw280]disp  dcb pfc interface 40ge  1/0/1

-------------------------------------------------------------------------------

Interface         Queue         Received(Frames)      Transmitted(Frames)     

-------------------------------------------------------------------------------

40GE1/0/1             3               1300155942               6073565259

-------------------------------------------------------------------------------

[~8006a-v-dsw280]disp  dcb pfc interface 40ge  1/0/1

-------------------------------------------------------------------------------

Interface         Queue         Received(Frames)      Transmitted(Frames)     

-------------------------------------------------------------------------------

40GE1/0/1             3               1300155944               6073565787

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