Re: [WIRELESS-LAN] Cisco APs losing CAPWAP session

[Dan Brisson]

It does seem as though I've grabbed some folks attention. I sure hope it turns out to not be something simple. :) I could certainly try moving the APs around...easy enough to do, although from what we've seen, the pattern of AP drops is so totally random, hard to say if I'll see anything.  At this point though, it's worth a shot. All interfaces clean and no QoS in place. Not sure if this will come through for everyone, but here's an example of what I see after an AP drops.  This is from the controller, on the General tab for an AP: Thanks, -dan Dan Brisson Network Engineer University of Vermont (Ph) 802.656.8111 dbris...@uvm.edu On 2/1/2012 9:26 AM, Garry Peirce wrote: I think you have some of us all getting curious! ;-) Could you put a historically stable admin AP onto the 5508 and vice-versa to see if behaviors change? Do we assume that all switchports in the path are showing they're running clean? Any QoS config in place on the switches? -----Original Message----- From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU] On Behalf Of Dan Brisson Sent: Wednesday, February 01, 2012 9:09 AM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: Re: [WIRELESS-LAN] Cisco APs losing CAPWAP session Good to know. The trunks are actually all 10Gig links, or 90% of them are, so utilization is most likely not the case, which I'm able to verify from Cacti graphs. The APs are connected to 3560Xs PoE switches that then uplink into either a 3560E-12D or directly into a 4900M where the 5508s are connected. Certainly can't rule out physical layer issue somewhere, although it's so wide spread across 2 different 5508s that we would need to have multiple issues. The other interesting thing for us is that the 500 or so APs on our admin side that do not lose their CAPWAP session, join to WiSMs, not 5508s. Thanks, -dan Dan Brisson Network Engineer University of Vermont (Ph) 802.656.8111 dbris...@uvm.edu On 1/31/2012 8:44 PM, Garry Peirce wrote: We have ~1400 (1240s->3502's) running 7.0.116 and have no such issues. I would guess at packet loss as well - some things you might look at: Are the trunks carrying user/AP traffic seem congested when the APs drop? Have you verified there are no duplex issues? It may exhibit itself more as traffic levels rise. ResHall switching significantly different than on the admin side? Probably need further topology, version, config info, but as you've a case open, the TAC will likely ask the same and help find the culprit(s) for you. -----Original Message----- From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU] On Behalf Of Dan Brisson Sent: Tuesday, January 31, 2012 8:30 AM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: [WIRELESS-LAN] Cisco APs losing CAPWAP session I'm curious if any Cisco users out there are experiencing or have experienced what we're seeing on our campus. This past summer we installed 3502i's in all of our residence halls - approximately 500 total. Ever since the students have moved in, we will get messages from WCS stating that "AP XYZ" is down and disassociated from the controller. When I check out the AP, the uptime is fine, but the "CAPWAP join time" is for like 30 seconds, or however long it took me to check. We've tracked this and it is totally random as to what AP will drop, which makes troubleshooting this very tough. The log on the AP isn't helpful. I'm working with TAC who suggests that keepalives are getting missed. I'm not sure why that would be the case since we have another 500 or so APs on the admin side that very rarely drop. Adding to that, when the students left for break, the AP drops stopped. They came back, and sure enough, the drops start up again. I will say that the AP always joins back immediately, but for the time that it does drop A) I'm sure connectivity is affected in that area and B) we get an email. Anyone experiencing this? Thanks, -dan -- Dan Brisson Network Engineer University of Vermont (Ph) 802.656.8111 dbris...@uvm.edu ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.