Certification793 problems· 22 reviewed

CCNA

793 incident response problems that help with CCNA prep.

All problems (793)

NETWORK-1482An Arista MLAG peer-link recovers and one VLAN still blackholesOne VLAN stays blackholed after MLAG recovery even though the peer-link and control plane are healthy.NetworkAdvanced12 minPro NETWORK-1490An EVPN type-5 route is present and traffic still missesOnly one tenant VRF misses a newly advertised external prefix during a staged EVPN rollout.NetworkAdvanced12 minPro NETWORK-1463An LACP bundle stays up and still blackholes one VLANOnly one VLAN experiences packet loss after a peer maintenance event while the bundle stays up.NetworkAdvanced12 minPro NETWORK-1405A branch office resolver sends a suffix zone to the wrong upstreamA branch office resolver sends a suffix zone to the wrong upstream focuses on dns and asks the reader to isolate the key signal in ubuntu. Resolver shortcuts can skip the one place where special-case validation behavior...NetworkAdvanced13 minPro NETWORK-1415A branch resolver forwards a private suffix correctly and DNSSEC failures...A branch resolver forwards a private suffix correctly and DNSSEC failures... focuses on dns and asks the reader to isolate the key signal in ubuntu. Resolver simplification can remove local exceptions that were silently making a broken u...NetworkAdvanced13 minPro NETWORK-1425A branch resolver forwards a private suffix correctly and DNSSEC failures...A branch resolver forwards a private suffix correctly and DNSSEC failures... focuses on dns and asks the reader to isolate the key signal in ubuntu. Resolver simplification can remove local exceptions that were masking upstream signature pr...NetworkAdvanced13 minPro NETWORK-1435A branch resolver forwards a private suffix correctly and DNSSEC failures...A branch resolver forwards a private suffix correctly and DNSSEC failures... focuses on dns and asks the reader to isolate the key signal in ubuntu. Resolver simplification can remove local exception logic that was silently masking u...NetworkAdvanced13 minPro NETWORK-1462A Cloudflare origin route stays green and one region still failsOne region sees random gRPC failures after an underlay tunnel change while global health stays green.NetworkAdvanced13 minPro NETWORK-1456A decryption bypass rule looks correct and still misses trafficTLS decryption bypass works for connection setup and later payloads start failing inspection on the same flow family.NetworkAdvanced13 minPro NETWORK-1445A DNS split-horizon migration works in direct queries and fails in appsInternal service names resolve in diagnostics and fail only behind one validating resolver chain.NetworkAdvanced13 minPro NETWORK-1429A new SaaS hostname is onboarded and only one campus failsA new SaaS hostname is onboarded and only one campus fails focuses on edge-routing and asks the reader to isolate the key signal in Cloudflare. New hostnames on shared CDNs can inherit old policy bundles long after DNS onboarding looks f...NetworkAdvanced13 minPro NETWORK-1419A new SaaS subdomain is onboarded to a shared CDN and only one campus failsA new SaaS subdomain is onboarded to a shared CDN and only one campus fails focuses on edge-routing and asks the reader to isolate the key signal in Cloudflare. On shared CDN platforms, a hostname can inherit an older policy bundle long after...NetworkAdvanced13 minPro NETWORK-1439A newly onboarded export hostname fails from one campusA newly onboarded SaaS export domain fails only from one policy-routed campus path.NetworkAdvanced13 minPro NETWORK-1449A newly onboarded export hostname fails from one campusA new export domain fails only from one campus path after a trust bundle update.NetworkAdvanced13 minPro NETWORK-1409A SaaS export endpoint fails only from one campusA SaaS export endpoint fails only from one campus focuses on edge-routing and asks the reader to isolate the key signal in Cloudflare. Shared CDN policy trees can misclassify new hostnames long after DNS looks correct everywhere else.NetworkAdvanced13 minPro NETWORK-1399A URL filtering exception covers the main SaaS host and file exports still...A URL filtering exception covers the main SaaS host and file exports still... focuses on incident-response and asks the reader to isolate the key signal in Palo Alto Networks. Feature-specific SaaS traffic often uses shared CDN hostna...NetworkAdvanced13 minPro NETWORK-1443An HA firewall pair syncs sessions and still breaks voiceVoice traffic survives failover and becomes unusable only on the standby-forwarded path.NetworkAdvanced13 minPro NETWORK-1441An HTTP/3 origin check passes in staging and fails in productionAn HTTP/3 origin check passes in staging and fails in production focuses on edge-routing and asks the reader to isolate the key signal in Cloudflare. Transport upgrades can change header normalization in ways signature code never anticipated.NetworkAdvanced13 minPro NETWORK-1455An NGINX stream SNI route sends traffic to the default upstreamA new privacy feature rollout sends traffic to the default upstream only on the stream ingress tier.NetworkAdvanced13 minPro NETWORK-1451An OSPF adjacency reaches two-way and still never advancesAn adjacency appears half-alive and never reaches full after a link refresh changed one side's interface defaults.NetworkAdvanced13 minPro