On the S5300EI, run the display qos port statistics interface interface-number command. The value of discard specifies the number of discarded packets.

        On the S3300HI&S5306HI&S5300HI&S6300, run the display qos queue statistics interface interface-number command. The value of discard specifies the number of discarded packets. If the value of the Dropped field is increasing, packets are lost because of congestion. You can load a patch or adjust the buffer to solve the problem.