By default, the Origin attribute of routes injected into BGP through the import-route command is Incomplete.

Question

Options

• ATRUE
• BFALSE

• A
  76% (39)
• B
  24% (12)

Explanation

Option A is correct because when routes are redistributed into BGP using the import-route command (or redistribute in some vendor implementations), BGP cannot determine the true origin of those routes - they came from outside the BGP domain - so it assigns the Incomplete (?) origin code, which has a value of 2. This is standard BGP behavior across all major vendors: only routes originated within BGP via the network command receive the IGP (i) origin attribute.

Option B is wrong because there is no scenario where import-route defaults to anything other than Incomplete; the Incomplete origin specifically exists to represent externally redistributed routes.

Memory tip: The three BGP Origin codes map to how "certain" BGP is about the route's source - IGP means BGP itself originated it (most trusted), EGP means it came from the old EGP protocol, and Incomplete means "I don't know exactly where this came from" - which is exactly what happens when you import a route from another protocol. Think: import = incomplete information = Incomplete origin.

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