Refer to the exhibit. The design is being proposed for use within the network. The CE devices are OSPF graceful restart-capable, and the core devices are OSPF graceful restart-aware. The WAN advertisements received from BGP are redistributed into OSPF. A forwarding supervisor failure event takes place on CE A. During this event, how will the routes learned from the WAN be seen on the core devices?

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C. via CE B OSPF graceful restart allows CE A to preserve its OSPF adjacencies with the core helper routers during the control-plane restart, but it does not protect BGP sessions on CE A. When the forwarding supervisor fails, CE A's BGP sessions reset, causing the previously redistributed WAN routes to be flushed from the LSDB. CE B's BGP sessions and OSPF redistribution remain fully operational throughout the event, so core devices continue to reach WAN prefixes exclusively via CE B.

Answer

A. via CE A and CE B CE A loses its BGP sessions during the supervisor failure, so its redistributed WAN routes are withdrawn even though OSPF graceful restart keeps the OSPF adjacency alive.

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B. via CE A CE A alone cannot be the path because the BGP-sourced routes it was redistributing are no longer in the LSDB after its BGP sessions drop.

Answer

D. no WAN routes will be accessible WAN routes remain fully reachable because CE B is unaffected by CE A's failure and continues redistributing its BGP-learned prefixes into OSPF.

Refer to the exhibit. The design is being proposed for use within the network. The CE devices are OSPF graceful restart-capable, and the core devices are OSPF graceful restart-aware. The WAN…

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