5-minute troubleshooting. Can you hear me?

Here I want to start new article series called “5-minute troubleshooting”. In these articles I’m going to describe short simple cases which we solved very quickly using protocol analysis and which could take much more time if we use another approach. So, let’s go.

One day we received an IP camera from our customer with the next complaint: “No image, no ping, the camera just disappeared from a network”.
First, we checked whether the camera was receiving PoE (yes it was), and booted up normally (according to camera LEDs no problems were here also).
Next step? Let’s try to ping it using IP-address our customer provided to us. No reply (and no surprise actually).
At this point it would be nice to check port statistics and status to eliminate L1 failure:

1_switch

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