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Multiple Switch Ports giving up/down alerts constantly

neillmcgarrigle
Level 1
Level 1

‎04-14-2022 06:53 AM

Hi Guys,

 

I have recently added a syslog to try rectify issues with two devices that were seeing connectivity issues. However since doing this i have noticed many switch ports going up/down all the time. Almost 700 entries in 24 hours. All of which are up/down alerts... However I am having no reports of any issues. The two devices that I was initally trying to tshoot are on Gi1/0/1 & GI1/0/2 but I can tshoot these at a later date as I suspect cabling for these two devices. I am however worries about the rest please see below

 

Apr 14 13:35:31.570: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet1/0/34, changed state to up
Apr 14 13:35:47.050: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet1/0/2, changed state to down
Apr 14 13:35:49.060: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet1/0/2, changed state to up
Apr 14 13:37:56.378: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet1/0/34, changed state to down
Apr 14 13:37:57.378: %LINK-3-UPDOWN: Interface GigabitEthernet1/0/34, changed state to down
Apr 14 13:38:01.167: %LINK-3-UPDOWN: Interface GigabitEthernet1/0/34, changed state to up
Apr 14 13:38:02.166: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet1/0/34, changed state to up
Apr 14 13:38:06.008: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet2/0/11, changed state to down
Apr 14 13:38:09.531: %LINK-3-UPDOWN: Interface GigabitEthernet2/0/11, changed state to down
Apr 14 13:38:12.523: %LINK-3-UPDOWN: Interface GigabitEthernet2/0/11, changed state to up
Apr 14 13:38:13.522: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet2/0/11, changed state to up
Apr 14 13:38:23.019: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet1/0/2, changed state to down

 

Port Align-Err FCS-Err Xmit-Err Rcv-Err UnderSize OutDiscards
Gi1/0/1 0 6286 0 16663 0 519
Gi1/0/2 0 9086 0 23871 0 519
Gi1/0/3 0 0 0 0 0 0
Gi1/0/4 0 0 0 0 0 0
Gi1/0/5 0 0 0 0 0 0
Gi1/0/6 0 0 0 0 0 0
Gi1/0/7 0 0 0 0 0 0
Gi1/0/8 0 0 0 0 0 23344
Gi1/0/9 0 0 0 0 0 0
Gi1/0/10 0 0 0 0 0 0
Gi1/0/11 0 0 0 0 0 3011
Gi1/0/12 0 0 0 0 0 0
Gi1/0/13 0 0 0 0 0 0
Gi1/0/14 0 0 0 0 0 0
Gi1/0/15 0 0 0 0 0 519
Gi1/0/16 0 0 0 1 0 4812
Gi1/0/17 0 0 0 0 0 0
Gi1/0/18 0 0 0 0 0 0
Gi1/0/19 0 0 0 0 0 0
Gi1/0/20 0 0 0 0 0 0
Gi1/0/21 0 0 0 0 0 0
Gi1/0/22 0 0 0 0 0 11560

Port Align-Err FCS-Err Xmit-Err Rcv-Err UnderSize OutDiscards
Gi1/0/23 0 0 0 0 0 6496
Gi1/0/24 0 0 0 0 0 0
Gi1/0/25 0 0 0 0 0 0
Gi1/0/26 0 0 0 0 0 12367
Gi1/0/27 0 9 0 15 0 95408
Gi1/0/28 0 0 0 0 0 14122
Gi1/0/29 0 0 0 0 0 0
Gi1/0/30 0 0 0 0 0 17618
Gi1/0/31 0 0 0 6 0 560725
Gi1/0/32 0 0 0 0 0 0
Gi1/0/33 0 0 0 0 0 16867
Gi1/0/34 0 1 0 6 0 138672
Gi1/0/35 0 0 0 0 0 606742
Gi1/0/36 0 16 0 24 0 173353
Gi1/0/37 0 0 0 0 0 23200
Gi1/0/38 0 0 0 0 0 0
Gi1/0/39 0 0 0 0 0 0
Gi1/0/40 0 0 0 19 0 3
Gi1/0/41 0 0 0 0 0 0
Gi1/0/42 0 0 0 0 0 0
Gi1/0/43 0 0 0 0 0 0
Gi1/0/44 0 0 0 0 0 0
Gi1/0/45 0 0 0 0 0 0
Gi1/0/46 0 0 0 0 0 0
Gi1/0/47 0 0 0 0 0 30124294
Gi1/0/48 0 0 0 0 0 19110
Gi1/0/49 0 0 0 0 0 7515
Gi1/0/50 0 0 0 0 0 4978
Gi1/0/51 0 0 0 0 0 6447
Gi1/0/52 0 0 0 0 0 0
Gi2/0/1 0 0 0 0 0 0
Gi2/0/2 0 0 0 0 0 0
Gi2/0/3 0 0 0 0 0 35509
Gi2/0/4 0 0 0 0 0 0
Gi2/0/5 0 0 0 0 0 0
Gi2/0/6 0 0 0 0 0 0
Gi2/0/7 0 0 0 0 0 0
Gi2/0/8 0 0 0 0 0 0
Gi2/0/9 0 0 0 0 0 0
Gi2/0/10 0 0 0 0 0 3
Gi2/0/11 0 0 0 0 0 32052
Gi2/0/12 0 0 0 1 0 5461
Gi2/0/13 0 0 0 0 0 16025
Gi2/0/14 0 0 0 0 0 575069
Gi2/0/15 0 0 0 0 0 26758
Gi2/0/16 0 0 0 0 0 0
Gi2/0/17 0 0 0 0 0 0
Gi2/0/18 0 0 0 1 0 769799
Gi2/0/19 0 7 0 14 0 1029667
Gi2/0/20 0 0 0 0 0 0
Gi2/0/21 0 0 0 0 0 170370
Gi2/0/22 0 0 0 0 0 0
Gi2/0/23 0 0 0 0 0 20784
Gi2/0/24 0 0 0 0 0 0
Gi2/0/25 0 0 0 0 0 0
Gi2/0/26 0 0 0 0 0 0
Gi2/0/27 0 0 0 0 0 0
Gi2/0/28 0 0 0 0 0 0
Gi2/0/29 0 0 0 0 0 0
Gi2/0/30 0 0 0 0 0 12402

Port Align-Err FCS-Err Xmit-Err Rcv-Err UnderSize OutDiscards
Gi2/0/31 0 0 0 0 0 0
Gi2/0/32 0 0 0 0 0 61157
Gi2/0/33 0 0 0 0 0 0
Gi2/0/34 0 0 0 0 0 0
Gi2/0/35 0 0 0 0 0 115732
Gi2/0/36 0 0 0 0 0 3
Gi2/0/37 0 0 0 0 0 0
Gi2/0/38 0 0 0 0 0 0
Gi2/0/39 0 0 0 0 0 0
Gi2/0/40 0 0 0 0 0 0
Gi2/0/41 0 0 0 0 0 3
Gi2/0/42 0 0 0 0 0 0
Gi2/0/43 0 0 0 0 0 0
Gi2/0/44 0 0 0 0 0 0
Gi2/0/45 0 0 0 0 0 0
Gi2/0/46 0 0 0 0 0 0
Gi2/0/47 0 0 0 0 0 245
Gi2/0/48 0 0 0 0 0 6649
Gi2/0/49 0 0 0 0 0 6670
Gi2/0/50 0 0 0 0 0 0
Gi2/0/51 0 0 0 0 0 4907
Gi2/0/52 0 0 0 0 0 0
Po1 0 0 0 0 0 25759
Po2 0 0 0 0 0 14185
Po3 0 0 0 0 0 4978
Po4 0 0 0 0 0 11354
Po5 0 0 0 0 0 0

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3 Replies 3

Flavio Miranda
VIP
VIP

‎04-14-2022 07:12 AM

 The fact that there´s no complain maybe is because the ups and downs is pretty fast and user may no realize that. For some traffic like web and email it may not cause great impact. But, voice and video could suffer with that.

 Actually, there are many events on the network that does not affect us but pops up on the syslog.  If you have time, you can go to the switch and investigate but this can be huge work load.

0 Helpful

MHM Cisco World
VIP
VIP

‎04-14-2022 08:43 AM

I think there is bottle neck here, 
you receive high rate traffic but the SW can not forward it and hence drop it. 

some of packet is necessary like BPDU this make SW port flapping.

0 Helpful

AnaGRojas
Level 1
Level 1
In response to MHM Cisco World

‎03-25-2024 08:43 AM

hello @MHM Cisco World, 

I am dealing with a situation similar to the one presented. So the possible solution that you propose is for the BPDU packets and would be to remove the command that makes that call.

I would appreciate it very much

0 Helpful
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