Certification793 problems· 22 reviewed

CCNA

793 incident response problems that help with CCNA prep.

All problems (793)

NETWORK-086IP SLA tracks the wrong probe target and withdraws the primary path during a healthy application incidentFailover triggers exactly as configured, but the chosen probe target does not represent the real application health and causes an unnecessary routing shift.NetworkAdvanced18 minPro NETWORK-089OSPF adjacency forms but area type mismatch suppresses the LSAs needed by the branch routeNeighbor status looks correct, yet the expected route never appears because one side treats the area differently and filters critical LSA propagation.NetworkAdvanced18 minPro NETWORK-1248A BGP session remains Established while one route class disappearsA peering stays up after a provider-side change and one business-critical route class vanishes from the local table.NetworkAdvanced19 minPro NETWORK-1243A BGP session remains Established while one route class vanishesA peering stays up after a provider change but one business-critical prefix set no longer enters the local table.NetworkAdvanced19 minPro NETWORK-1253A BGP session stays Established while one route class disappearsA provider-side change leaves the peering up while one set of business routes vanishes from the local table.NetworkAdvanced19 minPro NETWORK-1211BGP is Established but no prefixes arriveA new external BGP peer reaches Established immediately but no expected routes appear locally.NetworkAdvanced19 minPro NETWORK-1231BGP peering looks stable but only one prefix set disappearsA peer remains healthy and only one class of routes disappears after a provider-side policy change.NetworkAdvanced19 minPro NETWORK-093OSPF adjacency remains full but the summary route hides the more specific path needed for policy routingThe protocol is healthy, yet the application path fails because route summarization obscures the specific destination the policy logic depends on.NetworkAdvanced19 minPro NETWORK-1228Policy routing works for small flows but larger sessions dieA firewall and router pair pass small health checks, but file transfers or TLS handshakes break only on some sessions.NetworkAdvanced19 minPro NETWORK-1245A backup trunk becomes active during maintenance and one stack enters root-inconsistentA backup uplink that is almost never used is activated for maintenance and immediately destabilizes one access block.NetworkAdvanced20 minPro NETWORK-1235A cross-vendor trunk carries traffic for most VLANs but one access stack hits root-inconsistentA dormant backup uplink becomes active during maintenance and immediately places part of the access layer into an inconsistent spanning-tree state.NetworkAdvanced20 minPro NETWORK-1250A dormant backup trunk becomes active during maintenance and one stack enters root-inconsistentA maintenance failover onto an infrequently used trunk immediately causes root-inconsistent or blocked behavior in one stack.NetworkAdvanced20 minPro NETWORK-1255A dormant backup trunk becomes active during maintenance and one stack hits root-inconsistentA maintenance failover onto a backup trunk immediately causes root-inconsistent or blocked behavior in one access stack.NetworkAdvanced20 minPro NETWORK-1218BGP routes appear after reset but disappear againA peer begins showing routes after intervention, but the table empties again once normal policy evaluation resumes.NetworkAdvanced20 minPro NETWORK-1223BGP routes appear and disappearA route-map based on BGP community works right after reset and then loses routes during later convergence.NetworkAdvanced20 minPro NETWORK-1215Port-channel is up but throughput stays unevenA server uplink bundle stays up, but transfers still saturate strangely and only part of the expected member set carries flows.NetworkAdvanced20 minPro NETWORK-1220Intermittent packet loss follows only one ECMP pathA service sees sporadic failures only on some flows and packet captures show the issue correlates with one hashed path and larger payloads.NetworkAdvanced21 minPro NETWORK-1225Packet loss follows only jumbo frames on one uplinkLarge transfers fail unpredictably while ordinary traffic continues to work, and the failure follows only some hashed paths.NetworkAdvanced21 minPro NETWORK-1198BFD flap symptoms make BGP look unstable when the real issue is an aggressive keepalive path on one sideThe control plane appears unstable, but the real trigger is an overly aggressive liveness path that flaps faster than the underlying network can reliably support.NetworkAdvanced24 minPro NETWORK-1182OSPF adjacency never reaches FullA link migration leaves OSPF Hellos healthy, yet LSDB exchange never completes. Community threads point back to hidden interface MTU mismatch.NetworkAdvanced24 minPro