Re: Why AP cannot synchronize time from wlc sometimes

Leftz · ‎05-04-2021

Hi, New AP always has its self time, but when joining to wlc, it will get time from the wlc automatically. So we do not need to care about the time issue of the AP. But sometimes, although the AP can ping wlc, but it cannot synchronize its self time with the wlc, which means the ap still has its self time. That might cause issue to join to wlc. Why it happen? Thanks

marce1000 · ‎05-04-2021

- If you observe joining-issues , then post controller logs from that 'happening' and also ap-logs.

M.

-- Each morning when I wake up and look into the mirror I always say ' Why am I so brilliant ? '
When the mirror will then always repond to me with ' The only thing that exceeds your brilliance is your beauty! '

Leftz · ‎05-04-2021

Hi marce1000, Thank you very much for your reply. Actually this is a problem regarding ap(C9130 ap and C9800 wlc) joining wlc. Their version is pretty newer(wlc 17.3.3 and ap 8.10.130), but so far no big issue have been found out. The below are log for for both devices. Thank you

----- AP

*03/22/2021 04:50:28.7966] CAPWAP State: Discovery
[*03/22/2021 04:50:28.8013] Discovery Request sent to 10.2.9.16, discovery type STATIC_CONFIG(1)
[*03/22/2021 04:50:28.8056] Discovery Request sent to 10.2.9.16, discovery type STATIC_CONFIG(1)
[*03/22/2021 04:50:28.8073] Discovery Request sent to 255.255.255.255, discovery type UNKNOWN(0)
[*03/22/2021 04:50:58.2563]
[*03/22/2021 04:50:58.2563] CAPWAP State: Discovery
[*03/22/2021 04:50:58.2622] Discovery Request sent to 10.2.9.16, discovery type STATIC_CONFIG(1)
[*03/22/2021 04:50:58.2638] Discovery Request sent to 10.2.9.16, discovery type STATIC_CONFIG(1)
[*03/22/2021 04:50:58.2652] Discovery Request sent to 255.255.255.255, discovery type UNKNOWN(0)
[*03/22/2021 04:51:27.7178]
[*03/22/2021 04:51:27.7178] CAPWAP State: Discovery
[*03/22/2021 04:51:27.7377] Discovery Request sent to 10.2.9.16, discovery type STATIC_CONFIG(1)
[*03/22/2021 04:51:27.7395] Discovery Request sent to 10.2.9.16, discovery type STATIC_CONFIG(1)
[*03/22/2021 04:51:27.7410] Discovery Request sent to 255.255.255.255, discovery type UNKNOWN(0)
[*03/22/2021 04:51:57.1781]
[*03/22/2021 04:51:57.1781] CAPWAP State: Discovery
[*03/22/2021 04:51:57.1808] Discovery Request sent to 10.2.9.16, discovery type STATIC_CONFIG(1)
[*03/22/2021 04:51:57.1853] Discovery Request sent to 10.2.9.16, discovery type STATIC_CONFIG(1)
[*03/22/2021 04:51:57.1867] Discovery Request sent to 255.255.255.255, discovery type UNKNOWN(0)
[*03/22/2021 04:52:26.6378]
[*03/22/2021 04:52:26.6378] CAPWAP State: Discovery
[*03/22/2021 04:52:26.6412] Discovery Request sent to 10.2.9.16, discovery type STATIC_CONFIG(1)
[*03/22/2021 04:52:26.6429] Discovery Request sent to 10.2.9.16, discovery type STATIC_CONFIG(1)
[*03/22/2021 04:52:26.6443] Discovery Request sent to 255.255.255.255, discovery type UNKNOWN(0)

----------- WLC

May 4 02:08:02.268: %LINK-3-UPDOWN: Interface Vlan1, changed state to down
May 4 02:08:02.801: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet2, changed state to down
May 4 02:08:03.268: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to down
May 4 02:08:11.626: %LINK-3-UPDOWN: Interface GigabitEthernet2, changed state to up
May 4 02:08:12.461: %SYS-5-CONFIG_I: Configured from console by console
May 4 02:08:12.628: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet2, changed state to up
May 4 02:08:14.629: %LINK-3-UPDOWN: Interface Vlan1, changed state to up
May 4 02:08:15.630: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to up
May 4 02:08:15.635: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan239, changed state to up
May 4 02:12:10.767: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 02:15:31.332: %SYS-5-CONFIG_I: Configured from console by console
May 4 02:19:31.753: %LINK-3-UPDOWN: Interface GigabitEthernet3, changed state to up
May 4 02:19:32.756: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet3, changed state to up
May 4 02:19:41.877: %LINK-3-UPDOWN: Interface GigabitEthernet4, changed state to up
May 4 02:19:42.879: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet4, changed state to up
May 4 02:20:06.501: %SYS-5-CONFIG_I: Configured from console by console
May 4 02:23:14.463: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 02:23:16.447: %LINK-5-CHANGED: Interface GigabitEthernet2, changed state to administratively down
May 4 02:23:17.449: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet2, changed state to down
May 4 02:23:20.340: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 02:23:22.328: %LINK-5-CHANGED: Interface GigabitEthernet3, changed state to administratively down
May 4 02:23:23.329: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet3, changed state to down
May 4 02:24:29.756: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 02:24:34.821: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 02:24:36.812: %LINK-5-CHANGED: Interface GigabitEthernet4, changed state to administratively down
May 4 02:24:36.813: %LINK-3-UPDOWN: Interface Vlan1, changed state to down
May 4 02:24:36.815: %LINK-3-UPDOWN: Interface Vlan239, changed state to down
May 4 02:24:37.811: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet4, changed state to down
May 4 02:24:37.814: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to down
May 4 02:24:37.816: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan239, changed state to down
May 4 02:24:41.644: %LINK-3-UPDOWN: Interface GigabitEthernet2, changed state to up
May 4 02:24:42.647: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet2, changed state to up
May 4 02:24:44.647: %LINK-3-UPDOWN: Interface Vlan1, changed state to up
May 4 02:24:44.649: %LINK-3-UPDOWN: Interface Vlan239, changed state to up
May 4 02:24:45.646: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to up
May 4 02:24:45.649: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan239, changed state to up
May 4 02:25:22.206: %SYS-5-CONFIG_I: Configured from console by console
May 4 02:36:27.964: %SYS-6-TTY_EXPIRE_TIMER: (exec timer expired, tty 0 (0.0.0.0)), user
May 4 02:40:55.907: %WEBSERVER-5-SESS_TIMEOUT: Chassis 1 R0/0: : Session timeout from host 10.10.8.39 by user 'tadmin' using crypto cipher 'ECDHE-RSA-AES128-GCM-SHA256'
May 4 02:41:04.308: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: tadmin] [Source: 192.168.10.5] [localport: 21111] at 02:41:04 Eastern Tue May 4 2021
May 4 02:41:04.308: %WEBSERVER-5-LOGIN_PASSED: Chassis 1 R0/0: : Login Successful from host 10.10.8.39 by user 'tadmin' using crypto cipher 'ECDHE-RSA-AES128-GCM-SHA256'
May 4 02:46:20.487: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 02:46:31.528: %LINK-3-UPDOWN: Interface GigabitEthernet3, changed state to up
May 4 02:46:32.531: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet3, changed state to up
May 4 02:50:05.059: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 02:50:07.043: %LINK-5-CHANGED: Interface GigabitEthernet3, changed state to administratively down
May 4 02:50:08.043: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet3, changed state to down
May 4 02:50:15.753: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 02:52:02.408: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 02:52:05.382: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan239, changed state to up
May 4 03:07:31.569: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
.May 4 03:24:30.567: %SYS-6-TTY_EXPIRE_TIMER: (exec timer expired, tty 0 (0.0.0.0)), user
May 4 03:32:18.103: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 03:38:35.452: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 03:38:57.869: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 03:39:13.104: %SYS-6-TTY_EXPIRE_TIMER: (exec timer expired, tty 0 (0.0.0.0)), user
May 4 03:43:41.939: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet2, changed state to down
May 4 03:43:41.950: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 03:43:43.927: %LINK-3-UPDOWN: Interface Vlan1, changed state to down
May 4 03:43:44.927: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to down
May 4 03:43:49.645: %LINK-3-UPDOWN: Interface GigabitEthernet2, changed state to up
May 4 03:43:50.645: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet2, changed state to up
May 4 03:43:59.088: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 03:45:32.931: %LINK-5-CHANGED: Interface GigabitEthernet2, changed state to administratively down
May 4 03:45:32.943: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet2, changed state to down
May 4 03:45:32.954: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 03:45:39.647: %LINK-3-UPDOWN: Interface GigabitEthernet2, changed state to up
May 4 03:45:39.651: %LINK-3-UPDOWN: Interface Vlan1, changed state to up
May 4 03:45:40.648: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet2, changed state to up
May 4 03:45:40.651: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to up
May 4 03:49:58.873: %SYS-5-CONFIG_I: Configured from console by console
May 4 03:50:35.497: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet2, changed state to down
May 4 03:50:36.497: %LINK-3-UPDOWN: Interface Vlan1, changed state to down
May 4 03:50:37.496: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to down
May 4 03:50:39.502: %LINK-3-UPDOWN: Interface Vlan1, changed state to up
May 4 03:50:40.485: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet2, changed state to up
May 4 03:50:40.503: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to up
May 4 03:51:14.672: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan239, changed state to up
May 4 03:52:35.281: %SYS-5-CONFIG_I: Configured from console by console
May 4 04:03:41.297: %SYS-6-TTY_EXPIRE_TIMER: (exec timer expired, tty 0 (0.0.0.0)), user
May 4 05:28:13.384: %SMART_LIC-3-COMM_FAILED: Communications failure with the Cisco Smart License Utility (CSLU) : Unable to resolve server hostname/domain name
May 4 12:57:10.278: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: admin] [Source: 192.168.10.5] [localport: 21111] at 12:57:10 Eastern Tue May 4 2021
May 4 12:57:10.279: %WEBSERVER-5-LOGIN_PASSED: Chassis 1 R0/0: : Login Successful from host 10.10.8.56 by user 'admin' using crypto cipher 'ECDHE-RSA-AES128-GCM-SHA256'
May 4 13:27:23.588: %SMART_LIC-3-COMM_FAILED: Communications failure with the Cisco Smart License Utility (CSLU) : Unable to resolve server hostname/domain name
May 4 13:30:15.792: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as admin on vty0
May 4 13:30:29.846: %LINK-3-UPDOWN: Interface GigabitEthernet3, changed state to up
May 4 13:30:30.847: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet3, changed state to up
May 4 14:09:34.264: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: admin] [Source: 192.168.10.5] [localport: 21111] at 14:09:34 Eastern Tue May 4 2021
May 4 14:09:34.265: %WEBSERVER-5-LOGIN_PASSED: Chassis 1 R0/0: : Login Successful from host 10.1.36.109 by user 'admin' using crypto cipher 'ECDHE-RSA-AES128-GCM-SHA256'
May 4 14:14:20.034: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as admin on vty0
May 4 14:14:33.112: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as admin on vty0
May 4 14:15:08.610: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as admin on vty0
May 4 14:15:45.358: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as admin on vty0
May 4 14:16:13.456: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: admin] [Source: 10.10.8.56] [localport: 22] at 14:16:13 Eastern Tue May 4 2021
May 4 14:28:05.863: %SYS-6-TTY_EXPIRE_TIMER: (exec timer expired, tty 1 (10.10.8.56)), user admin
May 4 14:28:05.863: %SYS-6-LOGOUT: User admin has exited tty session 1(10.10.8.56)
May 4 14:41:20.568: %WEBSERVER-5-SESS_TIMEOUT: Chassis 1 R0/0: : Session timeout from host 10.10.8.56 by user 'admin' using crypto cipher 'ECDHE-RSA-AES128-GCM-SHA256'
May 4 14:45:15.667: %WEBSERVER-5-SESS_TIMEOUT: Chassis 1 R0/0: : Session timeout from host 10.10.8.58 by user 'admin' using crypto cipher 'ECDHE-RSA-AES128-GCM-SHA256'
May 4 14:45:28.994: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: admin] [Source: 192.168.10.5] [localport: 21111] at 14:45:28 Eastern Tue May 4 2021
May 4 14:45:28.995: %WEBSERVER-5-LOGIN_PASSED: Chassis 1 R0/0: : Login Successful from host 10.10.8.58 by user 'admin' using crypto cipher 'ECDHE-RSA-AES128-GCM-SHA256'
May 4 14:56:40.762: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: admin] [Source: 192.168.10.5] [localport: 21111] at 14:56:40 Eastern Tue May 4 2021
May 4 14:56:40.764: %WEBSERVER-5-LOGIN_PASSED: Chassis 1 R0/0: : Login Successful from host 10.10.8.56 by user 'admin' using crypto cipher 'ECDHE-RSA-AES128-GCM-SHA256'
May 4 14:57:03.229: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: admin] [Source: 10.10.8.56] [localport: 22] at 14:57:03 Eastern Tue May 4 2021
May 4 15:01:45.102: %SYS-5-CONFIG_I: Configured from console by admin on vty0 (10.10.8.56)
May 4 15:10:42.302: %WEBSERVER-5-SESS_LOGOUT: Chassis 1 R0/0: : Successfully logged out from host 10.10.8.56 by user 'admin' using crypto cipher 'ECDHE-RSA-AES128-GCM-SHA256'
May 4 15:13:13.626: %SYS-6-TTY_EXPIRE_TIMER: (exec timer expired, tty 1 (10.10.8.56)), user admin
May 4 15:13:13.627: %SYS-6-LOGOUT: User admin has exited tty session 1(10.10.8.56)
May 4 16:16:55.699: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: admin] [Source: 192.168.10.5] [localport: 21111] at 16:16:55 Eastern Tue May 4 2021
May 4 16:16:55.701: %WEBSERVER-5-LOGIN_PASSED: Chassis 1 R0/0: : Login Successful from host 10.2.4.222 by user 'admin' using crypto cipher 'ECDHE-RSA-AES128-GCM-SHA256'
May 4 16:31:46.155: %WEBSERVER-5-SESS_LOGOUT: Chassis 1 R0/0: : Successfully logged out from host 10.2.4.222 by user 'admin' using crypto cipher 'ECDHE-RSA-AES128-GCM-SHA256'
May 4 17:04:24.554: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: admin] [Source: 192.168.10.5] [localport: 21111] at 17:04:24 Eastern Tue May 4 2021
May 4 17:04:24.555: %WEBSERVER-5-LOGIN_PASSED: Chassis 1 R0/0: : Login Successful from host 10.10.8.56 by user 'admin' using crypto cipher 'ECDHE-RSA-AES128-GCM-SHA256'
May 4 17:29:24.279: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: tadmin] [Source: 192.168.10.5] [localport: 21111] at 17:29:24 Eastern Tue May 4 2021
May 4 17:29:24.280: %WEBSERVER-5-LOGIN_PASSED: Chassis 1 R0/0: : Login Successful from host 10.10.8.39 by user 'tadmin' using crypto cipher 'ECDHE-RSA-AES128-GCM-SHA256'
May 4 17:33:49.223: %WEBSERVER-5-SESS_TIMEOUT: Chassis 1 R0/0: : Session timeout from host 10.10.8.56 by user 'admin' using crypto cipher 'ECDHE-RSA-AES128-GCM-SHA256'
May 4 17:41:33.786: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 17:41:54.738: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet2, changed state to down
May 4 17:41:54.750: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 17:42:00.044: %LINK-3-UPDOWN: Interface GigabitEthernet2, changed state to up
May 4 17:42:01.044: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet2, changed state to up
May 4 17:42:14.054: %SYS-5-CONFIG_P: Configured programmatically by process SEP_webui_wsma_http from console as tadmin on vty0
May 4 18:02:04.218: %SYS-6-TTY_EXPIRE_TIMER: (exec timer expired, tty 0 (0.0.0.0)), user
May 4 18:02:53.352: %WEBSERVER-5-SESS_TIMEOUT: Chassis 1 R0/0: : Session timeout from host 10.10.8.39 by user 'tadmin' using crypto cipher 'ECDHE-RSA-AES128-GCM-SHA256'
May 4 18:21:53.207: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: admin] [Source: 10.10.8.56] [localport: 22] at 18:21:53 Eastern Tue May 4 2021

Leo Laohoo · ‎05-04-2021

APs always require a WLC to regularly synchronize their time.
When an AP boots up, AP will lose their time. This is expected.

saravlak · ‎05-04-2021

Generally, AP time shouldn't impact AP join at all, it's the controller time that matters for the AP. cert/d(TLS) cert exchange requires WLC time to be appropriate based on AP manufacturing date.

https://www.cisco.com/c/en/us/support/docs/wireless/5500-series-wireless-controllers/119286-lap-notjoin-wlc-tshoot.html

The controller will respond to all discovery requests without checking certificates or AP credentials. However, join requests must have a valid certificate in order to get a join response from the controller.

an example,
This information clearly shows that the controller time is outside the certificate validity interval of the AP. Therefore, the AP cannot register with the controller. Certificates installed in the AP have a predefined validity interval. The controller time should be set in such a way that it is within the certificate validity interval of the AP's certificate.