wlc 3504 DTLS connection closed forAP

[zeroken]

*spamApTask4: Jan 19 08:56:56.746: %CAPWAP-3-DTLS_CLOSED_ERR: capwap_ac_sm.c:7076 70:6d:15:0a:10:c0: DTLS connection closed forAP 10:10:1:204 (5248), Controller: 10:10:1:201 (5246) Echo Timer Expiry
*spamApTask2: Jan 19 08:56:56.746: %CAPWAP-3-DTLS_CLOSED_ERR: capwap_ac_sm.c:7076 00:b7:71:98:8c:60: DTLS connection closed forAP 10:10:1:202 (5248), Controller: 10:10:1:201 (5246) Echo Timer Expiry
*spamApTask2: Jan 19 08:56:56.745: %CAPWAP-3-ECHO_ERR: capwap_ac_sm.c:7821 Did not receive heartbeat reply; AP: 00:b7:71:98:8c:60
*spamApTask4: Jan 19 08:56:56.745: %CAPWAP-3-ECHO_ERR: capwap_ac_sm.c:7821 Did not receive heartbeat reply; AP: 70:6d:15:0a:10:c0
*spamApTask3: Jan 19 08:56:56.349: %CAPWAP-3-DTLS_CLOSED_ERR: capwap_ac_sm.c:7076 00:b7:71:b9:5b:00: DTLS connection closed forAP 10:10:1:203 (5248), Controller: 10:10:1:201 (5246) Echo Timer Expiry
*spamApTask5: Jan 19 08:56:56.349: %CAPWAP-3-DTLS_CLOSED_ERR: capwap_ac_sm.c:7076 70:6d:15:1c:9f:c0: DTLS connection closed forAP 10:10:1:205 (5256), Controller: 10:10:1:201 (5246) Echo Timer Expiry
*spamApTask3: Jan 19 08:56:56.348: %CAPWAP-3-ECHO_ERR: capwap_ac_sm.c:7821 Did not receive heartbeat reply; AP: 00:b7:71:b9:5b:00
*spamApTask5: Jan 19 08:56:56.348: %CAPWAP-3-ECHO_ERR: capwap_ac_sm.c:7821 Did not receive heartbeat reply; AP: 70:6d:15:1c:9f:c0
*spamApTask1: Jan 19 08:56:55.774: %CAPWAP-3-DTLS_CLOSED_ERR: capwap_ac_sm.c:7076 a0:b4:39:86:82:a0: DTLS connection closed forAP 10:10:5:80 (5256), Controller: 10:10:1:201 (5246) Echo Timer Expiry
*spamApTask3: Jan 19 08:56:55.070: %CAPWAP-3-DTLS_CLOSED_ERR: capwap_ac_sm.c:7076 70:6d:15:1c:a1:e0: DTLS connection closed forAP 10:10:5:250 (5256), Controller: 10:10:1:201 (5246) Echo Timer Expiry
*spamApTask2: Jan 19 08:56:53.358: %CAPWAP-3-DTLS_CLOSED_ERR: capwap_ac_sm.c:7076 70:6d:15:16:1e:00: DTLS connection closed forAP 10:10:4:250 (5272), Controller: 10:10:1:201 (5246) Echo Timer Expiry

WLC model. AIR-CT3504-K9

Cisco 3500 Series Wireless LAN Controller

Software Version 8.5.131.0

Cisco Bug: CSCvf76274 - Cisco APs can no longer join the WLC; CAPWAP-3-DTLS_DB_ERR

I have found some data that indicates that I have to update.
I would like to know if it is true that updating the wlc would solve the error.?

thanks

[marce1000]

 - The particular bug report does not correlate with the logs that you post. It seems that this AP has a flaky network connection and or no stable link to the controller, check accordingly.

 M.

[MHM Cisco World]

the AP not reachable to WLC,
check your WAN connect.

[Leo Laohoo]

Are you running HA SSO?