Propagation of BGP Updates
Now that you know enough about BGP to be dangerous, you should know that BGP announcements may take up to 20 minutes to be visible throughout the world. Although your peers should pick them up quickly, you can't expect that everybody everywhere is so well connected to you. After changing your BGP setup, wait at least 20 minutes to see what the real effects are before making another change. This will also help reduce the risk of being marked as a flapping BGP source and blackholing yourself off the Internet.
If you want to see how your BGP announcements are being viewed by the outside world, search the Internet for a "BGP Looking Glass." These are web pages that allow you to query routers for BGP information. By asking ...
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