我有一个带有 10gb 上游接口和 1gb 下游接口的接入交换机，我可以从 show interfaces [int] 看到流量在上游下游方向上被丢弃。

TenGigabitEthernet1/1 is up, line protocol is up (connected)
Hardware is Ten Gigabit Ethernet Port, address is f4cf.e213.7e30 (bia f4cf.e213.7e30)
Description: MATE.A01
MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec,
 reliability 255/255, txload 5/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 1000Mb/s, link type is auto, media type is 1000BaseSX
input flow-control is on, output flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:45, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 7556661
Queueing strategy: Class-based queueing
Output queue: 0/40 (size/max)
5 minute input rate 5364000 bits/sec, 1098 packets/sec
5 minute output rate 22402000 bits/sec, 2980 packets/sec
 863690200 packets input, 401065551603 bytes, 0 no buffer
 Received 6568826 broadcasts (1428513 multicasts)
 0 runts, 0 giants, 0 throttles
 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
 0 input packets with dribble condition detected
 2787171938 packets output, 1962145408543 bytes, 0 underruns
 0 output errors, 0 collisions, 4 interface resets
 0 unknown protocol drops
 0 babbles, 0 late collision, 0 deferred
 0 lost carrier, 0 no carrier
 0 output buffer failures, 0 output buffers swapped out

这些下降的原因很可能是由于流量从较高带宽接口流向较低带宽接口这一事实。缓冲区很快变满，交换机会丢弃一些数据包。

是否有一个命令可以让我看到数据包在缓冲区级别丢失？输出下降的原因是否更多？如何更详细地排除这些输出下降的故障？

谢谢