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Switches shows specific interfaces UP and DOWN just briefly every hour

jhussey
Level 1
Level 1

Hello,

I am not sure what the problem could be at a particular site.  I have 2 switches (3560 - 48 port) that have devices connected to them that require us to set the port settings to AUTO for them to connect.  At all the other locations that have this same setup as this site the ports don't flap and its strange that its happening on two different switches at the same site.  I have copied the output of the "sh log" command for each switch below that shows these ports flapping but I cannot seem to get a handle on the issue.

Do you think it’s the wiring that could be an issue since I don't believe both switches could be bad or their ports?

The logs from switch #1

Oct 22 06:36:49.735 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/14, changed state to down
Oct 22 06:36:50.742 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/14, changed state to down 
Oct 22 06:36:56.941 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/14, changed state to up   
Oct 22 06:36:59.474 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/14, changed state to down 
Oct 22 06:37:01.597 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/14, changed state to up   
Oct 22 06:37:02.603 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/14, changed state to up   
Oct 22 06:40:19.233 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/14, changed state to down
Oct 22 06:40:20.240 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/14, changed state to down  
Oct 22 06:40:22.362 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/14, changed state to up     
Oct 22 06:40:23.369 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/14, changed state to up  
Oct 22 06:52:09.300 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/14, changed state to down
Oct 22 06:52:10.306 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/14, changed state to down 
Oct 22 06:52:12.680 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/14, changed state to up  
Oct 22 06:52:13.687 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/14, changed state to up   
Oct 22 07:58:06.674 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/14, changed state to down 
Oct 22 07:58:08.687 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/14, changed state to up   
Oct 22 08:11:57.318 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/13, changed state to down 
Oct 22 08:11:59.332 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/13, changed state to up   
Oct 22 10:29:55.086 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/14, changed state to down 
Oct 22 10:29:56.092 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/14, changed state to down 
Oct 22 10:29:58.214 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/14, changed state to up  
Oct 22 10:30:01.713 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/14, changed state to up


The logs from switch #2

Oct 20 14:45:42.723 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/13, changed state to down               
Oct 20 14:45:46.607 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/13, changed state to up    
Oct 20 14:45:47.614 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/13, changed state to up  
Oct 20 22:49:11.913 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/28, changed state to down 
Oct 20 22:49:12.920 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/28, changed state to down
Oct 20 22:49:17.391 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/28, changed state to up  
Oct 20 22:49:18.398 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/28, changed state to up  
Oct 20 22:49:40.435 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/28, changed state to down
Oct 20 22:49:42.448 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/28, changed state to up  
Oct 21 07:46:32.447 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/12, changed state to down 
Oct 21 07:46:33.454 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/12, changed state to down 
Oct 21 07:46:35.535 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/12, changed state to up    
Oct 21 07:46:36.541 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/12, changed state to up  
Oct 21 08:01:32.715 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/13, changed state to down 
Oct 21 08:01:34.728 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/13, changed state to up  
Oct 21 09:34:56.775 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/28, changed state to down
Oct 21 09:34:57.782 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/28, changed state to down
Oct 21 09:35:02.337 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/28, changed state to up  
Oct 21 09:35:03.344 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/28, changed state to up 
Oct 21 09:35:25.590 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/28, changed state to down
Oct 21 09:35:27.604 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/28, changed state to up  
Oct 21 21:04:51.523 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/28, changed state to down
Oct 21 21:04:52.530 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/28, changed state to down 
Oct 21 21:04:57.085 EDT: %LINK-3-UPDOWN: Interface FastEthernet0/28, changed state to up  

3 Replies 3

Kimberly Adams
Level 3
Level 3

What do you have connected to these switchports and what does the running configuration of the ports look like?  This would be a big help.

Thanks,

Kimberly

Thanks and Cheers! Kimberly Please remember to rate helpful posts.

All the ports here are set to AUTO and they are connecting at a 100 MB / Full duplex.  The devices cannot be set to to anything other than AUTO and that is how it is at 100 other sites.

"connected    2     a-full  a-100 10/100BaseTX"

Do you think it could be the wiring that is at issue?

Can you swap the cables in the ports you think are having problems with another port and see if the problem follows the cable/device or stays with the switch port.

If it follows the device it could be either the wiring or the device. At that point I would swap the device with a known good one and see what happens.

- Brandon

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