- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
06-09-2018 01:12 PM - edited 07-05-2021 08:43 AM
Hi there
I have a Office connected to a Main office via a site2site running a Asa in both ends.
There are a Access point 2802, that are losing the connection to the WLC every 1 minute.
[*06/06/2018 02:36:44.1579] Warning, unencrypted data keepalive failed
[*06/06/2018 02:36:44.1579] Failed to receive data keepalive
[*06/06/2018 02:36:44.1580]
[*06/06/2018 02:36:44.1580] Lost connection to the controller, going to restart CAPWAP...
[*06/06/2018 02:36:44.1580]
[*06/06/2018 02:36:44.1580] Restarting CAPWAP State Machine.
Can it be a bug or a config issue ?
Mvh Mickey
Solved! Go to Solution.
- Labels:
-
Wireless LAN Controller
Accepted Solutions
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
09-03-2018 02:00 PM - edited 09-03-2018 02:00 PM
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
06-09-2018 04:13 PM
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
06-10-2018 11:51 AM
Its a WLC 3504 running version 8.5.120.0 and the accesspoint is a 2802.
Mvh Mickey
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
06-10-2018 04:57 PM
Attach the logs into the thread.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
09-03-2018 02:00 PM - edited 09-03-2018 02:00 PM
The solution was:
No _ in the AP group name.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
04-30-2020 09:31 AM
I have the same problem, did you use the command "no ap group name"?
What was the solution?

- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
08-19-2020 09:24 AM
Did you mean that we should not use "_" in the AP Group Name?
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
08-19-2020 09:31 AM - edited 08-19-2020 09:47 AM
From this old thread, yes it states the fix was not to use an underscore “_”.
*** Please rate helpful posts ***

- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
08-19-2020 09:55 AM - edited 08-19-2020 03:23 PM
Hi Scott,
thanks for answering, we are currently migrating our WIFI network to SD-WAN (which basically means IPSEC Tunneling), I have some AP's continuously sending me this:
*Aug 19 16:27:36.000: %CAPWAP-3-DATA_KEEPALIVE_ERR: Failed to receive data keep-alive *Aug 19 16:27:36.000: %DTLS-5-SEND_ALERT: Send FATAL : Close notify Alert to 10.0.0.1:5246
I check this post but the AP Group name configuration is not the case so I read the following article about CAPWAP Path MTU Discovery, so I am wondering if the additional encapsulation caused by SD-WAN devices in addition to CAPWAP could be the cause because from the AP showing those disconnections negotiated a MTU of 576 with the WLC instead of the maximum required one.
(Cisco Controller) >show ap config general APTESTING
Cisco AP Identifier.............................. 520
Cisco AP Name.................................... APTESTING
CAPWAP Path MTU.................................. 576
Cisco AP Group Name.............................. TESTINGACCESSPOINT
Primary Cisco Switch Name........................ WLC
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
08-19-2020 10:26 AM
*** Please rate helpful posts ***
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
06-12-2018 01:42 AM
https://www.cisco.com/c/en/us/support/docs/wireless/5500-series-wireless-controllers/113344-cuwn-ppm.html#anc8
Otherwise do what Leo suggested.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
04-20-2021 04:46 AM
Hi,
This happens in my environment as well but I don't have a solution yet. It only happens on a group of WAPs and not all of them. The AP group name i have is "default-group" any suggestions?
Thanks
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
03-22-2023 01:47 AM
Hi,
I had the same problem too but weirdly enough, the issue somehow resolved after I changed the cable from the AP to the switch. Hopefully this will help.
Thanks.
