BGP vs IGP

I’m not going to lie. The first time I used BGP it confused the crap out of me. If you come from an enterprise environment (like me) then you are probably pretty familiar with  how IGPs (for me it was OSPF) behave – if not how they work.

You insert a network statement and your IGP of choice starts working on all the interfaces within that network statement and hey presto – everything more or less straight up works. You don’t really need to understand how LSAs are propagated to get OSPF up and running.

Then one day you will undoubtedly have to configure BGP. BGP is a fairly different beast. The commands work differently, the protocol works differently.

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