Intepreting Cisco Switch and Router Logs - please help

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I am brand new to log analysis and I came across some Cisco Switch and Rout
er logs (that require me to analyse them). The logs contain 4 fields;the fi
rst three were easy to fathom (Datetime, error severity, source IP) but the
 fourth is not. I have scoured the internet looking for explanation but hav
e been unable to get any. Could somebody please explain what the following  
means, for example:

2464: 006077: Dec 28 22:35:12: %LINK-3-UPDOWN: Interface FastEthernet0/33,  
changed state to up
What do the numbers (2464, 006077) mean ? What does 'LINK-3-UPDOWN' mean ?  
What does 'changed state to up' mean ?


18312: 5w4d: %LINK-3-UPDOWN: Interface FastEthernet0/12, changed state to d
Many thanks in advance.

Re: Intepreting Cisco Switch and Router Logs - please help wrote:

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The numbers are an artefact of your logging system, though looking at  
the second line the second field looks like some kind of timestamp -  
uptime? time since logging started?

'LINK-3-UPDOWN' is a standard message tag in the style that Cisco put on  
(almost) all their log messages - Google is your friend.

If you don't know what 'up' and 'down' mean with regard to a switch  
interface then you probably need more training than we can offer you  


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