Hi all, I'm experiencing an issue with a WS-C3850-24S switch where a small percentage of packets are dropping from the output queues in about half of the trunks. I've done some research and found that it can be caused by an ingress interface that offers much more bandwidth than the egress interface. I'm not entirely sure this is what's causing it to be honest.
Ingress on this switch is a 2 x 10Gb EtherChannel trunk. Firmware version is 03.06.06E .
I've also tried to use some of the fixes described in these forums in regards to changing the queue parameters but have been unsuccessful in making those changes. I would really appreciate it if someone could help me out!
Trunk Interface stats:
reliability 255/255, txload 4/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not set
Full-duplex, 1000Mb/s, link type is auto, media type is 1000BaseBX-10U SFP
input flow-control is off, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:18, output never, output hang never
Last clearing of "show interface" counters 3w5d
Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 959239
Queueing strategy: fifo
Output queue: 0/40 (size/max)
30 second input rate 6068000 bits/sec, 2450 packets/sec
30 second output rate 18567000 bits/sec, 1655 packets/sec
147799652 packets input, 78574317037 bytes, 0 no buffer
Received 405149 broadcasts (136421 multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 136421 multicast, 0 pause input
0 input packets with dribble condition detected
237563053 packets output, 252406070491 bytes, 0 underruns
959239 output errors, 0 collisions, 0 interface resets
QoS Queue stats:
-------------------------------
Queue Buffers Enqueue-TH0 Enqueue-TH1 Enqueue-TH2
----- ------- ----------- ----------- -----------
0 0 0 0 1192754861
1 0 0 0 664465155
2 0 0 0 0
3 0 0 0 0
4 0 0 0 0
5 0 0 0 0
6 0 0 0 0
7 0 0 0 0
DATA Port:21 Drop Counters
-------------------------------
Queue Drop-TH0 Drop-TH1 Drop-TH2 SBufDrop QebDrop
----- ----------- ----------- ----------- ----------- -----------
0 0 0 0 0 0
1 0 0 3619155 0 0
2 0 0 0 0 0
3 0 0 0 0 0
4 0 0 0 0 0
5 0 0 0 0 0
6 0 0 0 0 0
7 0 0 0 0 0
AQM Broadcast Early WTD COUNTERS(In terms of Bytes)
--------------------------------------------------
PORT TYPE ENQUEUE DROP
--------------------------------------------------
UPLINK PORT-0 N/A 0
UPLINK PORT-1 N/A 0
UPLINK PORT-2 N/A 0
UPLINK PORT-3 N/A 0
NETWORK PORTS 21024980 140441674
RCP PORTS 0 0
CPU PORT 0 0
Note: Queuing stats are in bytes
