You want to configure your border leaf switches to leak routes between an overlay VRF named "dc1" and a VRF named "campus," which connects to the campus core. You also want to leak routes between an…

Question

Options

• Avrf dc1, import = 1:1, export = 1:99; vrf dc2, import = 1:2, export = 1:99; vrf campus, import = 1:99,
• Bvrf dc1, import = 1:1, export = 1:1; vrf dc2, import = 1:2, export = 1:2; vrf campus, import = 1:1, 1:2,
• Cvrf dc1, import = 1:99, export = 1:1; vrf dc2, import = 1:99, export = 1:2; vrf campus, import = 1:1,
• Dvrf dc1, import = 1:1, export = 1:1; vrf dc2, import = 1:1, export = 1:1; vrf campus, import = 1:1,

• A
  14% (6)
• B
  24% (10)
• C
  57% (24)
• D
  5% (2)

Explanation

Option C works because it uses a hub-and-spoke route-target design where each DC VRF has a unique export RT, while the campus VRF acts as the hub with a single shared export RT (1:99). dc1 exports 1:1 (campus imports it), dc2 exports 1:2 (campus imports it), and campus exports 1:99 - which both dc1 and dc2 import - creating bidirectional reachability to campus while keeping the DCs isolated from each other, since neither dc1 nor dc2 imports the other's unique export RT.

Option A breaks return path connectivity: dc1 and dc2 both export 1:99 and campus imports 1:99, so campus receives routes from both - but campus has no export RT that matches dc1's import (1:1) or dc2's import (1:2), so no routes can flow back from campus to the DCs.

Option B violates the isolation requirement: if campus imports both 1:1 and 1:2 and then exports those learned routes back with RTs that dc1 and dc2 import, dc1's routes transit through campus and leak into dc2 (and vice versa), breaking the dc1 ↔ dc2 isolation.

Option D is immediately disqualifying: dc1 and dc2 both use identical export and import RTs (1:1), so they directly import each other's routes and can communicate freely.

Memory tip: Think of option C as a "one-way funnel to campus" - each DC pours its routes into a unique pipe (1:1 or 1:2), but both DCs only hold the same key (1:99) to receive campus routes back. Since neither DC holds the other's key, they can't open each other's pipe.

No community discussion yet for this question.