BGP CCIE-ENTERPRISE-INFRASTRUCTURE Practice Questions (Page 6)

Questions 26–30

1. 26expert · hard

   A network engineer is configuring a new eBGP session between two routers that are connected via a firewall that does not allow IP packets with a TTL of 1. The engineer wants to establish the session using loopback interfaces. Which configuration is required on both routers to ensure the session comes up?

   • AUse only update-source loopback0 on both routers
   • BUse ebgp-multihop 2 and update-source loopback0 on both routers
   • CUse the neighbor's directly connected IP and disable TTL check
   • DUse only ebgp-multihop 2 on both routers
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2. 27expert · hard · select all that apply

   A network administrator is planning to implement BGP soft reconfiguration to avoid session resets when changing routing policies. The administrator wants to ensure that soft reconfiguration works for both inbound and outbound policy changes. Which statements are true regarding soft reconfiguration? (Select all that apply.)

   • ASoft reconfiguration inbound requires the router to store all received routes before policy is applied
   • BSoft reconfiguration outbound is always enabled by default
   • CSoft reconfiguration inbound is always enabled by default
   • DSoft reconfiguration outbound does not require storing routes
   • ERoute refresh capability allows a router to request re-advertisement of routes from a peer
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4. 28application · medium

   A dual-homed enterprise receives the same prefix from two ISPs. ISP A advertises the prefix with AS path 65001 65002 and local preference 200. ISP B advertises the same prefix with AS path 65001 and local preference 150. The enterprise router prefers the path from ISP A. Which BGP attribute is the primary reason for this preference?

   • ALocal preference
   • BMED
   • CWeight
   • DAS path length
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5. 29application · medium

   An enterprise router receives routes from a BGP peer and needs to filter out routes that contain the AS number 64512 in their AS path. The administrator wants to apply the filter only to inbound updates from that specific neighbor. Which configuration approach should be used?

   • AUse the neighbor's soft-reconfiguration inbound to manually filter
   • BUse a prefix-list to match the exact prefix and deny it
   • CSet the neighbor's route-reflector-client to avoid receiving the routes
   • DApply an AS-path access-list with a deny rule for regex '_64512_' in the neighbor's inbound route-map
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6. 30application · medium

   A multi-homed enterprise wants to influence inbound traffic from two upstream ISPs to prefer the primary link. The enterprise advertises the same prefix to both ISPs. The primary ISP is directly connected, and the backup ISP is two AS hops away. What is the most effective way to make the primary link preferred for inbound traffic?

   • ASet a higher local preference on the primary ISP's router
   • BPrepend the enterprise AS number multiple times on the backup ISP advertisement
   • CUse MED on the backup advertisement
   • DSet a lower weight on the backup ISP's router
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