Certification793 problems· 22 reviewed

CCNA

793 incident response problems that help with CCNA prep.

All problems (793)

NETWORK-1186Health checks fail from the load balancer subnet while user traffic still worksUsers can still reach the app, but the load balancer drains targets because health checks originate from a path the firewall policy never allowed.NetworkAdvanced22 minPro NETWORK-1210HTTPS health checks pass on one hostname while the real route failsAn edge service returns healthy responses to probes on one host name, while customers still see TLS errors on another.NetworkAdvanced22 minPro NETWORK-1196Source NAT hides the real client so ACL troubleshooting keeps focusing on the wrong segmentConnectivity appears blocked by an ACL on the destination side, but source NAT has already rewritten the path and the policy is evaluating a different source than operators expect.NetworkAdvanced22 minPro NETWORK-1194Firewall rule change looks correct but connection tracking keeps old assumptions aliveA rule update should allow new traffic, but live sessions still fail because connection tracking or stateful inspection has not re-evaluated the path the way operators expect.NetworkAdvanced23 minPro NETWORK-1204OSPF area design looks correct but summary routing hides one more specific path after migrationInter-area reachability mostly works, yet one destination disappears because a migrated summary route now masks the more specific path operators expected to win.NetworkAdvanced23 minPro NETWORK-1200Reverse proxy timeout tuning hides that one upstream path is serializing requests unexpectedlyRaising timeout values improves symptoms temporarily, but the real issue is that a supposedly parallel backend path became serialized and now stalls under modest load.NetworkAdvanced23 minPro NETWORK-1187VPN client injects a route that silently steals the return path for one private subnetGeneral connectivity remains healthy, but one internal subnet breaks because the host routing table now prefers a path injected by a VPN client.NetworkAdvanced23 minPro NETWORK-1192Anycast service flapsA route advertisement script taken from public examples checks process state only. Anycast traffic starts flowing before the node’s real dependency chain is ready.NetworkAdvanced24 minPro NETWORK-1189IOS XR eBGP session is up but policy omission means zero route exchangeThe BGP session establishes successfully, yet no routes move because an inbound or outbound policy required by the platform was omitted.NetworkAdvanced24 minPro NETWORK-1029A QoS policy marks the right classes (Timeouts and Latency)A QoS policy marks the right classes (Timeouts and Latency) focuses on Network Services And Operations and asks the reader to isolate Timeouts and Latency in Cisco. 실무에서는 Timeouts and Latency 이슈를 볼 때 DNS, 라우팅, ACL/방화벽, 목적지 응답을 계층별로 잘라서 확인하면 장애 구간을 훨씬 빠르게 좁힐 수 있습니다.NetworkAdvanced28 minPro NETWORK-1573A Cloudflare Access route is fixed and one service token still bypassesOne service token still bypasses new Access rules after route fixes.NetworkIntermediate8 minPro NETWORK-1583A Cloudflare origin route is fixed and one websocket still failsOne websocket path still fails after Cloudflare route corrections.NetworkIntermediate8 minPro NETWORK-1603A Cloudflare Tunnel route is correct and one app still loopsOne app still loops after a Cloudflare Tunnel route fix.NetworkIntermediate8 minPro NETWORK-1593A Cloudflare tunnel route is fixed and one origin still failsOne origin still fails after a Cloudflare tunnel route fix.NetworkIntermediate8 minPro NETWORK-1579A DHCP Option 82 template is updated and one relay still tags the old circuit idOne relay still tags the old circuit id after Option 82 template cleanup.NetworkIntermediate8 minPro NETWORK-1589A DHCP policy is corrected and one relay still inserts the old circuit-idOne relay still inserts the old circuit-id after policy correction.NetworkIntermediate8 minPro NETWORK-1609A DHCP relay change is correct and one site still hands out wrong leasesOne site still hands out wrong leases after a DHCP relay change.NetworkIntermediate8 minPro NETWORK-1599A DHCP relay template is updated and one switch still tags the old site codeOne switch still tags the old site code after DHCP relay template updates.NetworkIntermediate8 minPro NETWORK-1569A DHCP snooping template updates and one access switch still trusts the wrong uplinkOne access switch trusts the wrong uplink after snooping template updates.NetworkIntermediate8 minPro NETWORK-1586A dual-stack RA template is updated and one WLAN still prefers IPv4One SSID still prefers IPv4 after dual-stack template updates.NetworkIntermediate8 minPro