MSR56-60 v7.1.042R007p02 子接口drop

 572096015 packets output, 402488785477 bytes, 27271533 drops  ；

问题一、在子接口有应用出方向的qos(wred) ，怎么查看为什么有drop？

​interface GigabitEthernet2/5/3.506 

 bandwidth 9500 

ip address x.x.x.x

qos reserved-bandwidth pct 100 

qos apply policy QoS_default outbound 

vlan-type dot1q vid 506 

#

GigabitEthernet2/5/3 Current state: UP

 Line protocol state: UP 

 Interface Bandwidth: 1000000kbps

 Maximum Transmit Unit: 1500

1000Mb/s, Full-duplex, link type: autonegotiation,

  flow-control: disabled Output queue - 

Urgent queuing: Size/Length/Discards 0/100/0 Output queue - 

Protocol queuing: Size/Length/Discards 0/500/0 Output queue - 

FIFO queuing: Size/Length/Discards 0/75/177861526

 Last clearing of counters: 12:12:49 Wed 09/06/2017 

Last 300 seconds input rate: 3391976.00 bytes/sec, 27135808 bits/sec, 2850.45 packets/sec 

Last 300 seconds output rate: 474452.46 bytes/sec, 3795619 bits/sec, 560.89 packets/sec 

Input: 2379616170 packets, 4034688548 bytes 8821151 broadcasts, 17238424 multicasts, 0 pauses 0 errors, 0 runts, 0 giants 0 CRC, 0 overruns 0 drops, 0 no buffers 

 Output: 109451113 packets, 4270296458 bytes 5634 broadcasts, 0 multicasts, 0 pauses 0 errors, 0 underruns, 0 collisions 0 deferred, 0 lost carriers

GigabitEthernet2/5/3.506 

Current state: UP Line protocol state: UP 

 Bandwidth: 9500kbps

 Maximum Transmit Unit: 1500

Output queue - Urgent queuing: Size/Length/Discards 0/100/0

 Output queue - Protocol queuing: Size/Length/Discards 0/500/0 

Output queue - Class Based Queuing: Size/Discards 0/0 

 Queue size: EF/AF/BE 0/0/0 BE 

queues: Active/Max active/Total 0/0/256 AF queues:

 Allocated 6 Bandwidth(kbps): Available/Max reserve 2500/9500

 Last clearing of counters: 12:12:49 Wed 09/06/2017 

 7775040664 packets input, 10136215095565 bytes, 0 drops 

 572096015 packets output, 402488785477 bytes, 27271533 drops