I am brand new to this (Cisco Log Analysis) and I need some help with the meaning of Cisco Log messages. I have read a bit on the Cisco website and got up to speed but I need a bit of fine tuning so please indulge me.
Specifically, I have two lines pasted below from one of my logs.
2463: 006076: Dec 28 22:35:08: %LINK-3-UPDOWN: Interface FastEthernet0/33, changed state to down 2464: 006077: Dec 28 22:35:12: %LINK-3-UPDOWN: Interface FastEthernet0/33, changed state to up
The way I have understood it is that the first numbers are sequence numbers followed by the date stamp. After the % sign, there is the source, the severity and a mnemonic code that is related to the message, followed by the detailed message itself. In this case, severity '3' refers to 'error condition'
Question 1 - what would cause the link to change state to 'down' ? Question 2 - why should it be an 'error' when the interface changes state from down to up ?