we have c3850 trunk with other switch 4948 and its LACP 4x1G interface bonding (etherchannel) out of 4 1G we are getting
Total output drops on 2 interface.
This is all started yesterday when i upgrade software on this switch before that everything was good. doesn't make sense. I have done this upgrade on other switches to but no issue so far.
C3850#sh int g2/0/1 GigabitEthernet2/0/1 is up, line protocol is up (connected) Hardware is Gigabit Ethernet, address is 1c1d.86a9.3501 (bia 1c1d.86a9.3501) Description: coreSW_1_W_1of4_p MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec, reliability 255/255, txload 36/255, rxload 25/255 Encapsulation ARPA, loopback not set Keepalive set (10 sec) Full-duplex, 1000Mb/s, media type is 10/100/1000BaseTX input flow-control is off, output flow-control is unsupported ARP type: ARPA, ARP Timeout 04:00:00 Last input 00:00:11, 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: 133157273 Queueing strategy: fifo Output queue: 0/40 (size/max) 5 minute input rate 100659000 bits/sec, 61038 packets/sec 5 minute output rate 144390000 bits/sec, 76852 packets/sec 3445318149 packets input, 715126259616 bytes, 0 no buffer Received 827824 broadcasts (666658 multicasts) 0 runts, 0 giants, 0 throttles 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored 0 watchdog, 666658 multicast, 0 pause input 0 input packets with dribble condition detected 4521665906 packets output, 1080744400610 bytes, 0 underruns 133157273 output errors, 0 collisions, 1 interface resets 0 unknown protocol drops 0 babbles, 0 late collision, 0 deferred 0 lost carrier, 0 no carrier, 0 pause output 0 output buffer failures, 0 output buffers swapped out
C3850#sh int g2/0/1 counters Port InOctets InUcastPkts InMcastPkts InBcastPkts Gi2/0/1 718020111847 3459023952 668522 161527 Port OutOctets OutUcastPkts OutMcastPkts OutBcastPkts Gi2/0/1 1084965964251 4539489816 109940 86365
C3850#sh int g2/0/1 stats GigabitEthernet2/0/1 Switching path Pkts In Chars In Pkts Out Chars Out Processor 10458 2249522 0 0 Route cache 0 0 18985 2870366 Total 10458 2249522 18985 2870366
Our total utilization on link is 400Mbps, and i am seeing all link using around ~100 Mbps individually (few bytes here and there).
I am not seeing any performance issue on network. this trunk is connected to other switch and they are also running same speed interface 4x1G. I have upgrade multiple switch with same software and they all working fine without any interface error.