topic Re: Total output drops - C3750E in Network Security

Total output drops - C3750E

kasunrajapakse — Fri, 17 Apr 2020 14:58:56 GMT

Hi Team,

Can someone please let me know why I would see Total output drops increasing on this interface.

My issue is that there is a packet loss on traffic that travels via this interface. Could this be the reason?

I don't have QOS enabled.

SW3#show mls qos
QoS is disabled
QoS ip packet dscp rewrite is enabled

SW3#show interfaces gigabitEthernet 1/1/1
GigabitEthernet1/1/1 is up, line protocol is up (connected)
Hardware is Gigabit Ethernet, address is 6cfa.89a4.33b1 (bia 6cfa.89a4.33b1)
Description: to NE40 GigabitEthernet1/1/0
MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not set
Full-duplex, 1000Mb/s, link type is force-up, media type is unsupported
input flow-control is off, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:00, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 16100
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 2284000 bits/sec, 853 packets/sec
5 minute output rate 2508000 bits/sec, 780 packets/sec
60889537251 packets input, 21683685998473 bytes, 0 no buffer
Received 4102752170 broadcasts (2873581599 multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 2873581599 multicast, 0 pause input
0 input packets with dribble condition detected
62917540573 packets output, 34348192642702 bytes, 0 underruns
0 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
SW3#

Re: Total output drops - C3750E

Seb Rupik — Fri, 17 Apr 2020 15:13:53 GMT

Hi there,

This line is interesting:

Full-duplex, 1000Mb/s, link type is force-up, media type is unsupported

What is the output of:

sh inv

show interface transceiver

Have you tried using a cisco SFP in Gi1/1/1 ?

cheers,

Seb.

Re: Total output drops - C3750E

kasunrajapakse — Fri, 17 Apr 2020 15:18:32 GMT

Thanks for the quick reply Seb.

SW3#sh inv
NAME: "1", DESCR: "WS-C3750X-48"
PID: WS-C3750X-48T-S , VID: V06 , SN: FDO1714P1VH

NAME: "Switch 1 - Power Supply 1", DESCR: "FRU Power Supply"
PID: C3KX-PWR-350WAC , VID: V03D , SN: DCB170993GA

NAME: "Switch 1 - FRULink Slot 1 - FRULink Module", DESCR: "FRULink 1G Module"
PID: C3KX-NM-1G , VID: V01 , SN: FDO18151Z2N

NAME: "GigabitEthernet1/1/1", DESCR: "unsupported"
PID: , VID: 0473 , SN: EA124200231250

SW3#show interface transceiver
If device is externally calibrated, only calibrated values are printed.
++ : high alarm, + : high warning, - : low warning, -- : low alarm.
NA or N/A: not applicable, Tx: transmit, Rx: receive.
mA: milliamperes, dBm: decibels (milliwatts).

Optical Optical
Temperature Voltage Tx Power Rx Power
Port (Celsius) (Volts) (dBm) (dBm)
--------- ----------- ------- -------- --------
Gi1/1/1 38.8 3.26 -5.5 -6.0

Any advice?

Re: Total output drops - C3750E

balaji.bandi — Fri, 17 Apr 2020 15:18:36 GMT

type is force-up, media type is unsupported

what is the device connected ?

Re: Total output drops - C3750E

balaji.bandi — Fri, 17 Apr 2020 15:21:24 GMT

can you provide show version of the switch

show ver

show interfaces gigabitEthernet 1/1/1 transceiver details

show interfaces gigabitEthernet 1/1/1 capabilites.

Re: Total output drops - C3750E

kasunrajapakse — Fri, 17 Apr 2020 15:23:53 GMT

SW3#show interfaces gigabitEthernet 1/1/1 capabilities
GigabitEthernet1/1/1
Model: WS-C3750X-48
Type: unsupported
Speed: 1000
Duplex: full
Trunk encap. type: 802.1Q,ISL
Trunk mode: on,off,desirable,nonegotiate
Channel: yes
Broadcast suppression: percentage(0-100)
Flowcontrol: rx-(off,on,desired),tx-(none)
Fast Start: yes
QoS scheduling: rx-(not configurable on per port basis),
tx-(4q3t) (3t: Two configurable values and one fixed.)
CoS rewrite: yes
ToS rewrite: yes
UDLD: yes
Inline power: no
SPAN: source/destination
PortSecure: yes
Dot1x: yes
SW3#

SW3#show interfaces gigabitEthernet 1/1/1 transceiver detail
ITU Channel not available (Wavelength not available),
Transceiver is externally calibrated.
mA: milliamperes, dBm: decibels (milliwatts), NA or N/A: not applicable.
++ : high alarm, + : high warning, - : low warning, -- : low alarm.
A2D readouts (if they differ), are reported in parentheses.
The threshold values are calibrated.

High Alarm High Warn Low Warn Low Alarm
Temperature Threshold Threshold Threshold Threshold
Port (Celsius) (Celsius) (Celsius) (Celsius) (Celsius)
--------- ------------------ ---------- --------- --------- ---------
Gi1/1/1 38.9 85.0 75.0 0.0 -5.0

High Alarm High Warn Low Warn Low Alarm
Voltage Threshold Threshold Threshold Threshold
Port (Volts) (Volts) (Volts) (Volts) (Volts)
--------- --------------- ---------- --------- --------- ---------
Gi1/1/1 3.26 3.60 3.50 3.10 3.00

Optical High Alarm High Warn Low Warn Low Alarm
Transmit Power Threshold Threshold Threshold Threshold
Port (dBm) (dBm) (dBm) (dBm) (dBm)
--------- ----------------- ---------- --------- --------- ---------
Gi1/1/1 -5.5 -2.5 -3.5 -7.5 -8.5

Optical High Alarm High Warn Low Warn Low Alarm
Receive Power Threshold Threshold Threshold Threshold
Port (dBm) (dBm) (dBm) (dBm) (dBm)
------- ----------------- ---------- --------- --------- ---------
Gi1/1/1 -6.0 -3.0 -3.0 -19.0 -19.0

SW3#

Re: Total output drops - C3750E

Seb Rupik — Fri, 17 Apr 2020 15:28:17 GMT

What exactly is the product ID of the SFP connected to gi1/1/1 ?

There are some cases where SFPs only become supported in later IOS versions especially when using C3K-NM modules. What IOS version are you running on this switch?

cheers,

Seb.