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Cisco Bug: CSCul08933 - AP join fails with path MTU = 500

Last Modified

Jun 26, 2018

Products (1)

  • Cisco 5500 Series Wireless Controllers

Known Affected Releases


Description (partial)

Symptom:A lightweight AP fails to join its WLC, although it can ping the WLC.  The AP console shows the following errors:

*Oct 28 23:27:36.057: %CAPWAP-3-ERRORLOG: Go join a capwap controller
*Oct 28 23:27:38.000: %CAPWAP-5-DTLSREQSEND: DTLS connection request sent peer_ip: peer_port: 5246
*Oct 28 23:27:38.123: DTLS_CLIENT_ERROR: ../capwap/base_capwap/dtls/base_capwap_dtls_handshake.c:90 First fragment for seq 2 is missing
*Oct 28 23:27:38.124: DTLS_CLIENT_ERROR: ../capwap/base_capwap/dtls/base_capwap_dtls_handshake.c:90 First fragment for seq 2 is missing
*Oct 28 23:28:08.119: DTLS_CLIENT_ERROR: ../capwap/base_capwap/dtls/base_capwap_dtls_connection_db.c:2134 Max retransmission count reached!
*Oct 28 23:28:37.999: %DTLS-5-SEND_ALERT: Send FATAL : Close notify Alert to

Conditions:The IPv4 path between the WLC and the AP has an MTU of less than 576 (for example, 500.)

Related Community Discussions

Cisco 8500 WLC 3600/3700 AP DTLS ERRORS
Anyone deployed a 8500 and running into issues with 3600/3700 APs joining the WLC? WLC is connected to a nexus 5K via two 10GB ports. See  AP errors below...   *May 15 14:29:46.743: %LINEPROTO-5-UPDOWN: Line protocol on Interface Dot11Radio0, changed state to up *May 15 14:29:52.671: %CAPWAP-3-ERRORLOG: Selected MWAR 'WLC IP'(index 0). *May 15 14:29:52.671: %CAPWAP-3-ERRORLOG: Go join a capwap controller *May 15 14:31:53.000: %CAPWAP-5-DTLSREQSEND: DTLS connection request sent peer_ip: 10.X.X.X peer_port: ...
Latest activity: Jul 19, 2014
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