10Gbps link between FPR3130 and C9300-NM-8X keeps bouncing

[andrew.butterworth]

I have a 2 x 10Gbps port-channel using DAC cables (SFP-H10GB-CU3M) between a FPR3130 chassis ports Ethernet 9 & 10 and a C9300-24T with a C9300-NM-8X module ports Te1/1/1 & Te1/1/2.  The switch is constantly reporting the interface going down for about 5-seconds.  The interval between the bounces varies between 4-minutes and 61-minutes in the period I have been looking - so at least twice every hour.

I've replaced the DAC cable and the issue remains.  The FPR3130 chassis is running 7.4.2.2 which consists of FXOS 2.14(1.187) and firmware 1.4.102.  The chassis is in multi-instance mode and the FTD instances are running 7.4.2.3.  The switch is running IOS-XE 17.12.5.

My next step will be to move the cable to a spare SFP slot on the switch.  If that doesn't change anything, it will be moving it on the FPR3130 side.

I've had a dig through bugs, but can't see anything similar.  I'm hoping this isn't a hardware fault.

[MHM Cisco World]

Share 

Show play pm interface-flaps <interface>

This command run in SW

MHM

[andrew.butterworth]

I'm not sure how any of that information helps though.

I've also moved the SFP to a different slot on the switch so this is the old interface that is now down.

[MHM Cisco World]

The port is flapping because 

1- mismatch speed or duplex 

2- over heat of transceiver 

Are you sure this port now connect to FPR ?

MHM

[Mark Elsen]

 @andrew.butterworth  Check logs , both on the cisco and fpr device. Also look at interface counters on both platforms ,

 M.

[andrew.butterworth]

The bounces have now stopped after moving it to Te1/1/3 on the C9300-NM-8 module.  Could be a faulty module?

[MHM Cisco World]

Keep monitor the link' if it not down again then it issue of module.

MHM

[Mark Elsen]

  - @andrew.butterworth    Ref : https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst9300/software/release/17-10/configuration_guide/sys_mgmt/b_1710_sys_mgmt_9300_cg.pdf
                                         Start reading from Chapter 7 for executing diagnostics.

  N,

[johnlloyd_13]

hi,

did you just move the switch side to port tengig port 3 and used the same cable?

if yes, then probably the previous module port could be "dead". if this is the case, raise a TAC RMA.

[andrew.butterworth]

The interface flaps have returned, but not as frequent.  The interface was moved on the switch side from Te1/1/1 to Te1/1/3 on Friday 25th July.  Looking in the logs this morning I can see five up/down events starting at 02:47 on Sunday 27th July.

Jul 27 02:47:24.554: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet1/1/3, changed state to down
Jul 27 02:47:29.601: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet1/1/3, changed state to up
Jul 27 04:39:36.358: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet1/1/3, changed state to down
Jul 27 04:39:41.339: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet1/1/3, changed state to up
Jul 27 06:38:46.161: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet1/1/3, changed state to down
Jul 27 06:38:51.156: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet1/1/3, changed state to up
Jul 27 20:09:43.081: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet1/1/3, changed state to down
Jul 27 20:09:47.989: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet1/1/3, changed state to up
Jul 28 07:46:11.155: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet1/1/3, changed state to down
Jul 28 07:46:16.071: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet1/1/3, changed state to up

 The output of the 'show platform pm interface-flaps ten1/1/3 shows 'No.of LinkDownEvents : 17'

I guess I'll need to move it on the FPR3130 side and see what happens.

[MHM Cisco World]

these log not showing anything it for low level Admin 
check this link 

https://www.cisco.com/c/en/us/support/docs/switches/catalyst-9500-series-switches/218397-troubleshoot-port-flaps-on-catalyst-9000.html

debug pm xxx <<- this can give you more detail about what make port flapping 

also 

check speed and duplex of FPR side 

MHM