Spanning Tree Protocol Troubleshooting: Part 1

 


The suggested troubleshooting order begins with determining which router is the HSRP (Hot Standby Routing Protocol). I did this by going the CLI in R1 and finding the following:

The preemption enabled tells me that this will be the active router–if the priority is higher than the other option, which it is.  R1 is 110, and R2 is 100.  
The next Step is to ping 203.0.113.9 (SP1) from both PCs. I used the command prompt to do this.


After that, I check the Layer 3 path using traceroute. The correct command is tracert not tracecert!  

The layer 3 path is good, so I now know to look at layer 2–which is evident if you consider this is an STP lab. For real-world applications, I would need to check layer three first.  

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