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CCNA 200-301 v1.1 reference — Network Access

Wireless client troubleshooting

Diagnose client connectivity failures from controller and client configuration evidence: security, VLAN, band and RF causes.

Objective 2.9Objective 1.11v1.1 exam target
Quick ReferenceHandbook
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Where client connectivity fails

  1. Association: is the client associated to a BSSID/SSID at all?
  2. Authentication: does PSK/802.1X succeed?
  3. IP: does the client lease an address in the right VLAN?
  4. Connectivity: gateway, then beyond — same as wired verification.

Evidence → likely cause

ObservationPoints to
SSID not visible in scan listWLAN disabled, AP not broadcasting, band mismatch (client lacks the band)
Association/auth fails immediatelySecurity mismatch — wrong PSK, 802.1X vs PSK confusion, PMF requirement unmet
Associated, but no IP / APIPAVLAN/DHCP path broken — wrong WLAN-interface map, missing helper, exhausted scope
Associated + IP but no gatewayWrong VLAN delivered, or the SVI is down
Connects but constant drops/slownessRF: interference, weak RSSI, channel overlap, power/band issues

Security/band mismatches to check

Client capabilityWLAN requirementResult
WPA2-only clientWPA3-required WLANCannot authenticate
Client missing PMFWLAN requires 802.11w PMFAssociation fails
2.4 GHz-only client5/6 GHz-only SSIDSSID invisible to that client
Legacy clientWPA3 transition/mixed modeUsually works — transition mode allows WPA2
Read a client symptom correctly
Symptom
Client joins 'CORP', gets 169.254.x.x
Context
Other clients on the same AP work
  1. 169.254.x.x means the client associated and authenticated — radio and security are fine.
  2. DHCP broadcast never got an offer on this WLAN — but peers on the same AP work.
  3. Different result on the same AP → suspect a different SSID/VLAN mapping or a client-side DHCP quirk, not the RF.

Trace the DHCP path for that specific WLAN→VLAN mapping; the AP itself is healthy.

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Handbook sections

Related resources

Practise this topicSource topic 55: Wireless FundamentalsPractise topic 55 deckSource topic 56: Wireless Architectures (CAPWAP & WLC)Practise topic 56 deckSource topic 57: Wireless Security (WPA2/WPA3 & 802.1X)Practise topic 57 deckSource topic 58: Wireless ConfigurationPractise topic 58 deck

Sources

Targets CCNA 200-301 v1.1 objectives. Supplemental blocks are labeled beyond exam scope.

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