In the TechTarget article Border Gateway Protocol (BGP) troubleshooting: Advanced approach
I'm describing how to troubleshoot BGP connectivity in a customer network with a single BGP-speaking router connected to upstream ISPs.
You can practice the skills described in that article on NIL's remote labs. Cisco partners and employees can get them free of charge on Partner E-learning connection: just click this link after logging into PEC. Everyone else can buy the same labs as part of IP Routing bundle from NIL Data Communications.
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